Liquid crystal display panel and its manufacturing method

ABSTRACT

A liquid crystal display panel, in which a first substrate ( 1 ) and a second substrate ( 6 ) are opposed to each other with a predetermined gap provided therebetween, a liquid crystal layer ( 25 ) is sealed in the gap with a sealant ( 26 ), pixel portions are formed by electrodes ( 2, 7 ), the electrodes being provided on the first substrate ( 1 ) and on the second substrate ( 6 ) to oppose to each other via the liquid crystal layer ( 25 ), and lead electrodes ( 41 ) for applying electric signals to the electrodes ( 2, 7 ) forming the pixel portions are provided at least on the first substrate ( 1 ), wherein a thin film insulating layer ( 22 ) being an insulating covering member is provided to cover at least portions of the lead electrodes ( 41 ) outside the sealant ( 26 ) and overlap with a portion of the second substrate ( 6 ).

TECHNICAL FIELD

[0001] The present invention relates to a liquid crystal display panelcharacterized in a structure for preventing electrolytic corrosion oflead electrodes for applying electric signals to electrodes formingpixel portions, and a method for fabricating such a liquid crystaldisplay panel.

BACKGROUND TECHNOLOGY

[0002] Conventionally, a liquid crystal display panel has been used inwhich a first substrate and a second substrate are opposed to each otherwith a predetermined gap provided therebetween, a liquid crystal layeris sealed in the gap with a sealant, pixel portions are formed byelectrodes, the electrodes being provided on the substrates to oppose toeach other via the liquid crystal layer, and lead electrodes forapplying electric signals to the electrodes forming the pixel portionsare provided at least on the first substrate. In such a liquid crystaldisplay panel, the electric signals applied to the electrodes formingthe pixel portions change optical characteristics of the liquid crystallayer to control ON/OFF states of the pixel portions for performance ofdisplay.

[0003] The configuration of such a conventional liquid crystal displaypanel will be described using FIG. 41 to FIG. 43 taking, as an example,a reflective liquid crystal display panel for use in a cellular phone, apersonal digital assistant, a timepiece, and the like. FIG. 41 is a planview of the conventional liquid crystal display panel, FIG. 42 is across-sectional view taken along a line 42-42 shown in FIG. 41, and FIG.43 is a partially enlarged plan view of a part (in circle C) in FIG. 41.

[0004] This liquid crystal display panel is, as shown in FIG. 41, amatrix-type liquid crystal display panel having m stripe firstelectrodes 2 provided on a first substrate 1 and n stripe secondelectrodes 7 provided on a second substrate 6, and a display region 23constituted of m by n pixel portions 24 being intersections of the firstelectrodes 2 and the second electrodes 7. The first substrate 1 and thesecond substrate 6 are opposed to each other with a predetermined gapprovided therebetween with not-shown spacers and are bonded togetherwith a sealant 26 as shown in FIG. 42, and a liquid crystal layer 25 issealed in the gap and hermetically sealed with a closing member 27 sothat hermeticity is ensured.

[0005] Further, as shown in FIG. 42, a reflector 16 composed of analuminum film or a silver alloy film is provided on the second substrate6, and a color filter which is composed of a red (R) color filter 17, agreen (G) color filter 18, and a blue (B) color filter 19 is provided onthe reflector 16. Thereon, a flattening protective film 21 is providedto flatten projections and depressions of the color filter and preventan electrical short circuit between the reflector 16 and the secondelectrodes 7, and the second electrodes 7 are provided on the flatteningprotective film 21. Furthermore, on the first electrodes 2 and on thesecond electrodes 7, alignment films (not shown) are provided to alignliquid crystal molecules in the liquid crystal layer 25 in predetermineddirections.

[0006] By the way, in this liquid crystal display panel, as shown inFIG. 41, the first substrate 1 is made larger in size than the secondsubstrate, and a driving integrated circuit (IC) 36 for applying drivingsignals to the first electrodes 2 and driving ICs 35 for applyingdriving signals to the second electrodes 7 are mounted on the firstsubstrate 1. Note that the second substrate 6 is made to have a sizelarger than the display region 23 and not to reach a region where thedriving ICs 35 and 36 are provided on the first substrate 1.

[0007] Then, lead electrodes continued to the first electrodes 2 forconnecting the first electrodes 2 and the driving IC 36 are led out fromthe display region 23 to the outside of the sealant 26. On the leadelectrodes, the driving IC 36 is mounted through an anisotropicconductive film containing conductive particles in a polyimide resin,and the film is compressed by heat to cure, so that the first electrodes2 are connected to the driving IC 36 through the lead electrodes.

[0008] Further, lead electrodes 41 for connecting the second electrodes7 and the driving ICs 35 are provided on the first substrate. A portionof the sealant 26 is composed of an anisotropic conductive sealantcontaining conductive particles in an acrylic resin, and a pressure isapplied to the second substrate 6 and the first substrate 1 through theanisotropic conductive sealant, so that the second electrodes 7 providedon the second substrate 6 are electrically conducted through theconductive particles to the lead electrodes 41 provided on the firstsubstrate 1. Then, the driving ICs 35 are mounted on the lead electrodes41 similarly to the case of the above-described driving IC 36, so thatthe second electrodes 7 are connected to the driving ICs 35 through thelead electrodes 41.

[0009] Further, to apply signals to the driving ICs 35 and 36 from anexternal circuit, a flexible printed circuit board (FPC) 31 connected tothe driving ICs 35 and 36 through connecting electrodes 42 shown in FIG.42 and FIG. 43 is provided. Note that the FPC 31 and the driving ICs 35and 36 are connected to the connecting electrodes 42 through ananisotropic conductive film.

[0010] In such a conventional liquid crystal display panel, as shown inFIG. 43, an insulating resin 32 is applied to a portion where the leadelectrodes 41 are provided on the first substrate 1 to preventoccurrence of a potential difference between adjacent lead electrodes 41and adherence of contamination or moisture thereto. As this insulatingresin 32, an epoxy resin having low moisture permeability or a siliconresin having low moisture absorbability is used.

[0011] However, in a fabrication process of a liquid crystal displaypanel body, a mounting process of the driving integrated circuits 35, ora mounting process of the FPC 31, if contamination adheres thereto,pinholes form in the insulating resin 32, or the insulating resin 32 hasan insufficient moisture blocking property, the electrode material melts(is corroded) at a portion of the lead electrode 41 to create anelectrolytically corroded portion 47 as shown in FIG. 43, finally givingrise to a phenomenon that the lead electrode 41 is broken, when theliquid crystal display panel is driven for a long time or in anatmosphere at a high temperature and high humidity. Therefore, when theelectrolytically corroded portion 47 is created, the driving signalsfrom the driving ICs 35 and 36 cannot be transmitted to electrodesconstituting the pixel portion 24, which makes it impossible to performintended display, and as a result, the display quality of the liquidcrystal display panel is significantly reduced.

[0012] The connecting electrode 42 for establishing connection with theFPC 31 can have an electrode width and gap between electrodes which arelarger than those of the lead electrode 41 and thus can be structured tobe relatively insusceptible to electrolytic corrosion. On the otherhand, the lead electrode 41 has to have a small electrode width and gapbetween electrodes to increase the pixel density within the displayregion 23 and thus becomes susceptible to electrolytic corrosion.

[0013] Therefore, it is very important to prevent the electrolyticallycorroded portion 47 from being created in the lead electrode 41 evenwhen the liquid crystal display panel is used in the atmosphere at ahigh temperature and high humidity, in order to increase the usablerange of the liquid crystal display panel and keep good display qualityfor a long time. Besides, since there is a strong demand for a reductionin size and cost of the liquid crystal display panel, it is alsoimportant to prevent the electrolytically corroded portion 47 from beingcreated without greatly departing from the thickness and size of theconventional liquid crystal display panel and with suppressing anincrease in cost and weight to a minimum. More than that, anelectrolytic corrosion preventing structure is necessary which can copewith various kinds of methods for connecting lead electrodes to externalcircuits and driving ICs.

[0014] It should be noted that a structure shown in FIG. 44 is also wellknown as a connecting structure for preventing moisture entrance into aconnecting portion in a flat display panel in which an FPC is directlyconnected to a lead electrode.

[0015] This flat display panel is a thin film EL (electro luminescent)display panel in which a lead electrode 94 provided on a glass substrate91 is bonded and connected to an FPC 95 with a solder 96, a resin 97 isfilled in a region including the connecting portion on the glasssubstrate 91, and further a protective glass plate 98 is disposed on theresin 97.

[0016] The protective glass 98 provided on the resin 97 as describedabove can decrease the area of the resin 97 in contact with air andprevent moisture entrance into the lead electrode 94 and corrosion ofthe lead electrode 94.

[0017] Even in this structure, however, it is conceivable that moistureenters through between a rear glass substrate 92 and the protectiveglass plate 98, and thus it cannot be said that the structure issufficient in moisture blocking property and accordingly electrolyticcorrosion preventing ability.

[0018] It is an object of the present invention to solve such problemsand greatly reduce occurrence of electrolytic corrosion at a leadelectrode using a simple technique with the size and weight of aconventional liquid crystal display panel being secured.

DISCLOSURE OF THE INVENTION

[0019] In order to attain the above object, the liquid crystal displaypanel of the invention is a liquid crystal display panel, in which afirst substrate and a second substrate are opposed to each other with apredetermined gap provided therebetween, a liquid crystal layer issealed in the gap with a sealant, pixel portions are formed byelectrodes, the electrodes being provided on the first substrate and onthe second substrate to oppose to each other via the liquid crystallayer, and lead electrodes for applying electric signals to theelectrodes forming the pixel portions are provided at least on the firstsubstrate, wherein an insulating covering member is provided to cover atleast portions of the lead electrodes outside the sealant and overlapwith a portion of the second substrate.

[0020] In such a liquid crystal display panel, it is preferable to mountan integrated circuit element on the lead electrodes, and provide theinsulating covering member also on the integrated circuit element.

[0021] Besides, in addition to that or in stead of that, it ispreferable to provide a flexible connecting board connected to theintegrated circuit element, and provide the insulating covering memberalso at least on a portion of the flexible connecting board.

[0022] Alternatively, it is also adoptable that the insulating coveringmember is provided on both faces of the flexible connecting board, alsoon a side face of the second substrate, or also on a side face of thefirst substrate or on a face of the first substrate opposite to a faceprovided with the lead electrodes.

[0023] Besides, it is also adoptable that a polarizing film is providedon at least one of the first substrate and the second substrate, and theinsulating covering member is provided also on the polarizing film oralso between the polarizing film and the substrate provided with thepolarizing film.

[0024] Further, it is also adoptable that a reflecting layer is providedon one of the first substrate and the second substrate.

[0025] Besides, in such a liquid crystal display panel, it is preferablethat an insulating resin is provided on the insulating covering member.Further, it is adoptable that a second insulating covering member isprovided on the insulating resin.

[0026] Besides, it is preferable that the insulating covering member isan insulating layer formed in a vacuum condition, and is an insulatinglayer containing silicon or an insulating layer made of metal oxide.

[0027] Further, it is preferable that the insulating covering member issmaller in thickness than the liquid crystal layer.

[0028] Further, it is preferable that the insulating covering member hasa structure in which two or more different kinds of insulating films arelaminated.

[0029] Furthermore, it is preferable that the insulating covering memberis 200 nm to 500 nm in thickness.

[0030] The liquid crystal display panel of the invention is theabove-described liquid crystal display panel, in which an insulatingresin is provided to cover at least portions of the lead electrodesoutside the sealant, and the insulating covering member is providedthereon.

[0031] In such a liquid crystal display panel, it is preferable that aportion where the first substrate, the insulating resin, the secondsubstrate, and the insulating covering member overlap one another asseen from the first substrate side, is provided.

[0032] Besides, it is also adoptable that the first substrate and theinsulating covering member are bonded together with the insulatingresin, or that the insulating covering member is bonded to both thefirst substrate and the second substrate with the insulating resin.

[0033] Besides, in such a liquid crystal display panel, it is alsoadoptable to mount an integrated circuit element on the lead electrodes,and provide the insulating resin between the integrated circuit elementand the sealant.

[0034] Further, it is preferable that the insulating covering member hasportions overlapping with the insulating resin, the integrated circuitelement, and the second substrate, respectively as seen from the firstsubstrate side, or that the insulating covering member is in contactwith both the integrated circuit element and the second substrate.

[0035] Besides, it is preferable to provide a flexible connecting boardfor connecting the integrated circuit element and an external circuit.In this case, it is preferable that the insulating covering member hasportions overlapping with the insulating resin, the second substrate,and the flexible connecting board, respectively as seen form the firstsubstrate side, or that the insulating covering member has portionsoverlapping with the insulating resin, the integrated circuit element,the second substrate, and the flexible connecting board, respectively asseen form the first substrate side.

[0036] Alternatively, it is also adoptable to provide a flexibleconnecting board directly connected to the lead electrodes. In thiscase, it is preferable that the insulating covering member has portionsoverlapping with the insulating resin, the second substrate, and theflexible connecting board, respectively as seen form the first substrateside.

[0037] Besides, in the above-described liquid crystal display panel, itis preferable that the insulating resin is composed of at least twokinds of resins, or that the insulating covering member has a thermalexpansion coefficient equal to that of the first substrate or the secondsubstrate.

[0038] Besides, it is also adoptable to provide a polarizing film, anduse the polarizing film as the insulating covering member. It is alsoadoptable that the insulating covering member is provided to be incontact with the polarizing film. It is also adoptable that theinsulating covering member is provided to be in contact with thepolarizing film.

[0039] In the above liquid crystal display panel, it is preferable thatthe insulating covering member is formed of glass, plastic, ceramics, ormetallic material. Further, it is preferable to provide a gas barrierlayer or a moisture blocking layer.

[0040] Further, it is preferable that a second insulating coveringmember is provided on the insulating covering member, and the secondinsulating covering member is an anodic oxide layer of the metallicmaterial.

[0041] Besides, it is preferable that the insulating resin isconstituted of an epoxy resin, an ultraviolet curing resin, or a siliconresin, and it is also adoptable that the insulating resin has a lightabsorption material.

[0042] It is preferable that the insulating resin is composed of a firstinsulating resin for covering at least portions of the lead electrodesand a second insulating resin for sealing a space formed by the firstinsulating resin, the first substrate, and the second substrate.

[0043] Besides, it is preferable that the insulating covering member hasa face in contact with the insulating resin and in a directionperpendicular to the first substrate.

[0044] Then, it is preferable that the insulating covering member isprovided with an opening. In this case, it is preferable that theopening is provided at a portion not overlapping with the leadelectrodes. Besides, it is preferable that the opening is an opening forintroducing the insulating resin, and the insulating resin has a swollenstructure in the opening.

[0045] Besides, it is also adoptable that the insulating covering memberhas a U-shaped cross section and is provided such that the firstsubstrate is in contact with inside of the letter U. In this case, it ispreferable that the insulating covering member is in contact with atleast two faces out of six faces being top and bottom, right and left,and front and back faces of the first substrate, that the insulatingcovering member is provided with a substrate groove for fitting thefirst substrate therein, or that a flexible connecting board forconnecting the liquid crystal display panel to an external circuit isprovided, and the insulating covering member is provided with an openingfor passing the flexible connecting board therethrough.

[0046] Alternatively, in the above-described liquid crystal displaypanel, it is preferable to provide a flexible connecting board forconnecting the liquid crystal display panel to an external circuit, andprovide the insulating resin also at least on respective portions ofboth faces of the flexible connecting board.

[0047] Alternatively, it is preferable that the insulating coveringmember is composed of a black member and is used as a panel cover to beprovided on an outer periphery of a display region constituted of thepixel portions.

[0048] Besides, it is also adoptable to provide a flexible connectingboard for connecting the liquid crystal display panel to an externalcircuit, and use a portion of the flexible connecting board as theinsulating covering member.

[0049] Alternatively, it is preferable that an outer shape of the secondsubstrate aligns with an outer shape of the sealant at least on a sidewhere the lead electrodes are led out to the outside of the sealant.

[0050] It is also adoptable that a second insulating covering member isprovided on the insulating covering member.

[0051] Besides, in the above-described liquid crystal display panel, itis preferable to mount an integrated circuit element on the leadelectrodes, and provide the insulating covering member also on theintegrated circuit element and color it in black on the integratedcircuit element.

[0052] Alternatively, it is preferable that an outer peripheral wall forpreventing the insulating resin from flowing out is provided on at leasta portion of an outer periphery of a region where the insulating resinis to be provided.

[0053] Besides, it is preferable that the insulating covering member isprovided in a plurality of divided parts.

[0054] It is preferable that the insulating covering member is 80 μm to150 μm in thickness.

[0055] Besides, a method for fabricating a liquid crystal display panelof the invention includes: a step of preparing a liquid crystal displaypanel in which a first substrate and a second substrate are opposed toeach other with a predetermined gap provided therebetween, a liquidcrystal layer is sealed in the gap with a sealant, pixel portions areformed by electrodes, the electrodes being provided on the firstsubstrate and on the second substrate to oppose to each other via theliquid crystal layer, and lead electrodes for applying electric signalsto the electrodes forming the pixel portions are provided at least onthe first substrate; a step of mounting an integrated circuit element ora flexible connecting board on the lead electrodes; a resin applyingstep of applying an insulating resin onto the lead electrodes at leastoutside the sealant; an insulating covering member disposing step ofdisposing an insulating covering member on the insulating resin to coverat least portions of the lead electrodes outside the sealant and overlapwith a portion of the second substrate; and a curing step of curing theinsulating resin, the steps being performed in this order.

[0056] In such a method for fabricating a liquid crystal display panel,it is preferable to provide, prior to the insulating covering memberdisposing step, a step of disposing a polarizing film on the firstsubstrate or on the second substrate.

[0057] Alternatively, it is preferable to provide, between theinsulating covering member disposing step and the curing step, alow-viscosity insulating resin applying step of applying a low-viscosityinsulating resin lower in viscosity than the insulating resin to seal aspace formed by the insulating resin, the first substrate, and thesecond substrate, wherein the curing step is a step of curing theinsulating resin and the low-viscosity insulating resin.

[0058] Alternatively, it is preferable to provide, prior to the resinapplying step, a low-viscosity insulating resin applying step ofapplying a low-viscosity insulating resin lower in viscosity than theinsulating resin to at least a portion of a space between the firstsubstrate and the second substrate outside the sealant.

[0059] Further, it is preferable to provide, between the low-viscosityinsulating resin applying step and the resin applying step, alow-viscosity insulating resin curing step of curing the low-viscosityinsulating resin.

[0060] Besides, in the method for fabricating a liquid crystal displaypanel, it is preferable to provide, prior to the resin applying step, anouter peripheral wall setting step of providing an outer peripheral wallfor preventing the insulating resin from flowing out on at least aportion of an outer periphery of a region to which the insulating resinis to be applied.

[0061] A method for fabricating a liquid crystal display panel of theinvention includes: a step of preparing a liquid crystal display panelin which a first substrate and a second substrate are opposed to eachother with a predetermined gap provided therebetween, a liquid crystallayer is sealed in the gap with a sealant, pixel portions are formed byelectrodes, the electrodes being provided on the first substrate and onthe second substrate to oppose to each other via the liquid crystallayer, and lead electrodes for applying electric signals to theelectrodes forming the pixel portions are provided at least on the firstsubstrate; a step of mounting an integrated circuit element or aflexible connecting board on the lead electrodes; and an insulatingcovering member forming step of forming an insulating covering member bya vacuum sputtering or a chemical deposition (CVD) method to cover atleast portions of the lead electrodes outside the sealant and overlapwith a portion of the second substrate, the steps being performed inthis order.

[0062] In such a method for fabricating a liquid crystal display panel,it is preferable that the insulating covering member forming step isperformed at a temperature equal to or lower than 150° C.

[0063] Besides, it is preferable to provide, prior to the insulatingcovering member forming step, a polarizing film disposing step ofdisposing a polarizing film on the first substrate or on the secondsubstrate.

[0064] Further, it is preferable that the polarizing film disposing stepis a step of disposing a polarizing film having a protective film, andto provide, after the insulating covering member forming step, a step ofremoving the protective film of the polarizing film.

[0065] Besides, in the above-described method for fabricating a liquidcrystal display panel, it is preferable to provide, prior to theinsulating covering member forming step, a step of performing for atleast a region where the insulating covering member is to be provided aplasma treatment using any one of an oxygen plasma, an inert gas such asan argon gas, an oxygen gas, and a nitrogen gas, or a mixture gas of twoor more kinds of these.

[0066] The liquid crystal display panel of the invention in such astructure that the lead electrodes to be provided at least on the firstsubstrate are led out to the outside from the inside of the sealantsealing the liquid crystal layer, employs the structure, as describedabove, in which the insulating covering member composed of the thin filminsulating layer is provided to cover at least the portions of the leadelectrodes outside the sealant and overlap with a portion of the secondsubstrate, in order to prevent the material of the lead electrodes frombeing electrolyzed (electrolytically corroded) by an electric currentgenerated by application of a voltage between adjacent lead electrodescaused by moisture adhering onto the lead electrodes. It is preferableto use, as the thin film insulating layer, a dense film with no moisturepermeability and capable of being formed at 100° C. to 200° C.

[0067] This thin film insulating layer, which is formed not only on thelead electrodes but also on the integrated circuit element and sidefaces thereof, and, in addition, on a boundary between the leadelectrodes and the integrated circuit element, enables better preventionof moisture permeation.

[0068] When a tape automated bonding (TAB) is performed, or when thefirst substrate or the second substrate is connected to a flexibleconnecting board (flexible printed circuit board: FPC) or a circuitboard in which circuits are formed on a plastic substrate, the moisturepermeability can be made very low by providing the thin film insulatinglayer on the tape carrier package, FPC, or plastic substrate as well ason the electrodes on the first substrate or the second substrate.

[0069] Further, the insulating resin composed of the epoxy resin or thesilicon resin is provided on the thin film insulating layer, whichenables prevention of physical breakage of the thin film insulatinglayer and enhancement of prevention of electrolytic corrosion. Besides,the thin film insulating layer can be made dense and low in moisturepermeability by employing a single film or laminated films of a siliconnitride film, a silicon oxide film, or silicon nitride oxide film as thethin film insulating layer.

[0070] Further, a thin film insulating layer composed of metal oxidesuch as a tantalum oxide film, a titanium oxide film, or the like can beused to form a dense film at a low temperature, which allows use ofsubstrates or mounted members low in resistance temperature.

[0071] Although ultraviolet rays might be generated when such a film isformed, the liquid crystal layer can be protected from the generatedultraviolet rays by providing the thin film insulating layer afterbonding a polarizing film having an ultraviolet cutting layer, so thatthe thin film insulating layer can be formed without particularprotection of the liquid crystal layer. Further, since moisturepermeation into the polarizing film can be prevented by forming the thinfilm insulating layer in the above-described order and providing thethin film insulating layer also on the polarizing film, the reliabilityof the polarizing film can be improved.

[0072] Further, since the surface of the sealant or closing membersealing the liquid crystal layer can also be covered with the thin filminsulating layer if it is formed by the vacuum sputtering or the CVDmethod, moisture permeation into the liquid crystal layer can beprevented, which makes it possible to improve the reliability of theliquid crystal display panel and to keep the display quality constant.

[0073] When, as in a reflective liquid crystal display device, areflector for blocking ultraviolet rays or a member for absorbingultraviolet rays as the color filter is provided on the side of thesubstrate facing the liquid crystal layer, this member can preventirradiation of ultraviolet rays to the liquid crystal layer. There is noneed to limit, in particular, the portion where the thin film insulatinglayer is to be formed, and thus a configuration in which the thin filminsulating layer is provided also on a display face facilitates theformation of the thin film insulating layer.

[0074] Further, use of a plastic substrate (film substrate) as thesubstrate is more effective because the thin film insulating layer candecrease the moisture permeability of the substrate to prevent moisturepermeation into the liquid crystal layer. Further, when the thin filminsulating layer is formed on both the first substrate and the secondsubstrate, almost all the surfaces of the plastic substrate can becovered with the thin film insulating layer, so that the reliability canbe improved.

[0075] Further, in a two-layered structure composed of the thin filminsulating layer and the insulating resin, a multi-layered thin filminsulating layer, or a three-layered structure composed of the thin filminsulating layer, the insulating resin, and the second thin filminsulating layer, pinholes penetrating all of them hardly form, whichcan decrease variation of the reliability. Further, for prevention ofpinhole formation in the thin film insulating layer, repetition of stepsof film formation of the thin film insulating layer, surface cleaning,and film formation a plurality of times can effectively prevent thepinhole formation.

[0076] When the liquid crystal display panel is used under a harshcondition, the glass substrate, the plastic substrate, or the secondinsulating covering member composed of a covering member whose surfaceis subjected to insulation treatment is provided on a portionoverlapping with the lead electrodes formed with the thin filminsulating layer, in order to prevent flaw of the thin film insulatinglayer and improve the hydrophobic property in the lead electrodes. Whena covering member thicker than the thin film insulating layer is used,the covering member can be made low in moisture permeability and keepthe state of the low moisture permeability because a flaw or the likegenerated by an external force never penetrates the covering member withease.

[0077] Here, such a method is also conceivable that the insulating filmis formed in advance on the first substrate 1 as a structure forsuppressing occurrence of an electrolytically corroded portion. However,when the insulating film is formed before a so-called cell forming stepof providing a gap between the first substrate and the second substrate,bonding them with the sealant, and sealing the liquid crystal layertherein, it is necessary to remove the insulating film and form contactholes at predetermined positions in order to establish electricalconnection between bump electrodes of the driving integrated circuit andthe electrodes on the first substrate 1, but this step requirespositional accuracy and thus it is difficult to perform by a printingmethod. Therefore, a photolithography step and an etching step arerequired, which leads to increased cost. Further, the accuracy of thephotolithography step and etching step depends on the material of theinsulating film, giving rise to a problem that etching at a highaccuracy is difficult to perform for a material suitable for preventingelectrolytic corrosion. In contrast to this, the insulating coveringmember composed of the thin film insulating layer for use in theinvention does not need such a photolithography step and etching step,and thus can be easily formed for prevention of electrolytic corrosion.

[0078] Besides, the liquid crystal display panel of the invention alsoemploys a structure in which a covering member is provided as theabove-described insulating covering member. In this case, the insulatingresin is provided to cover at least the portions of the lead electrodesoutside the sealant, and the covering member is provided thereon.

[0079] The covering member for use here can be a plastic plate having apredetermined thickness, a glass plate, a metal plate, a substratecomposed of a metal plate provided with an anodic oxide layer as asecond insulating covering member, a ceramic plate, or a laminatedbonded material. These are very low in moisture permeability and not afilm formed by application as the insulating resin, so that formation ofbubbles and pinholes therein can be greatly reduced.

[0080] In the case of the plastic plate, by providing a gas barrierlayer such as a silicon oxide film, a silicon nitride film, or analuminum oxide film, or a moisture blocking film composed of a moisturebarrier layer, moisture entrance into the lead electrodes can be greatlydecreased.

[0081] Besides, when the integrated circuit element (IC) for driving theliquid crystal display panel is mounted on the lead electrodes providedon the first substrate by the Chip on Glass (COG) mounting method, ifthe covering member is provided with the second substrate and the IC asa screen, a gap between the first substrate and the covering member canbe made uniform. Moreover, by applying the insulating resin to the faceof the IC opposite to the face in contact with the lead electrodes andthe second substrate and bonding the covering member thereto, thecovering member can be securely held.

[0082] Further, a conductive film, for example, a transparent conductivefilm or the like provided on the face of the covering member opposite tothe face in contact with the IC can realize not only prevention ofmoisture permeation into the lead electrodes but also reduction ofelectrostatic shock to the IC at the same time.

[0083] Besides, when the FPC is bonded onto the first substrate with theanisotropic conductive film by application of a pressure, electrolyticcorrosion of the FPC connecting portion in contact with the FPC can beconcurrently prevented by providing the covering member on the leadelectrodes and on the anisotropic conductive film.

[0084] Further, when the first insulating resin is applied onto the leadelectrodes provided on the first substrate, and the second insulatingresin, different in characteristics from the first insulating rein, isapplied to the face in contact with the covering member, that is,between the first insulating resin and the covering member, even a resinincapable of being applied thick because it has a large stress, or aninsulating resin taking a long curing time due to the existence of thecovering member, as the first insulating resin on the first substrateside, becomes usable. Furthermore, even an insulating resin which curesin a very short time as of an ultraviolet curing type can be used as thesecond insulating resin.

[0085] Besides, when the driving integrated circuit of the liquidcrystal display panel is directly mounted on portions of the leadelectrodes provided on the first substrate by the COG method, if a lightabsorbing material is mixed into the insulating resin, an increase inpower consumption and malfunction of the IC due to the light can beprevented. Further, use of a material having a light shielding propertyas the covering member can extremely limit the light passage into the ICin the liquid crystal display panel.

[0086] Besides, for securer hermeticity by the insulating resin and thecovering member, it is preferable to provide the second insulatingresin, which is lower in viscosity than the first insulating resin, in aspace near the sealant formed by the first substrate, the secondsubstrate, and the sealant. As a result, the first insulating resinhaving a high viscosity forms a bank on the periphery, while the secondinsulating resin having a low viscosity can be made to permeate into thespace securely and to bond to the covering member.

[0087] Furthermore, it is possible that a covering protector which isadjacent to the covering member, overlaps with a portion of the firstsubstrate, and has a face also in a direction of a cross section sidewall of the first substrate, is provided at the outer peripheral portionof the first substrate, to prevent the insulating resin from flowingdown and reduce non-application of the insulating resin in the spacebetween the first substrate and the second substrate.

BRIEF DESCRIPTION OF DRAWINGS

[0088]FIG. 1 is a plan view of a liquid crystal display panel of a firstembodiment of the present invention;

[0089]FIG. 2 is a cross-sectional view taken along a line 2-2 shown inFIG. 1;

[0090]FIG. 3 is a partially enlarged plan view showing a part in circleA in FIG. 1;

[0091]FIG. 4 is a cross-sectional view, corresponding to FIG. 2, showinga cross section of a liquid crystal display panel of a second embodimentof the invention;

[0092]FIG. 5 is a partially enlarged plan view, corresponding to FIG. 3,showing a part near lead electrodes of the same;

[0093]FIG. 6 is a cross-sectional view, corresponding to FIG. 4, showingthe configuration of a modified example of the liquid crystal displaypanel of the second embodiment of the invention;

[0094]FIG. 7 is a cross-sectional view, corresponding to FIG. 2, showinga cross section of a liquid crystal display panel of a third embodimentof the invention;

[0095]FIG. 8 is a cross-sectional view, corresponding to FIG. 2, showinga cross section of a liquid crystal display panel of a fourth embodimentof the invention;

[0096]FIG. 9 is a plan view of a liquid crystal display panel of a fifthembodiment of the invention;

[0097]FIG. 10 is a cross-sectional view taken along a line 10-10 in FIG.9;

[0098]FIG. 11 is a cross-sectional view taken along a line 11-11 in FIG.9;

[0099]FIG. 12 is a cross-sectional view, corresponding to FIG. 2,showing a cross section of a liquid crystal display panel of a sixthembodiment of the invention;

[0100]FIG. 13 is a cross-sectional view, corresponding to FIG. 2,showing a cross section of a liquid crystal display panel of a seventhembodiment of the invention;

[0101]FIG. 14 is a plan view of a liquid crystal display panel of aneighth embodiment of the invention;

[0102]FIG. 15 is a cross-sectional view taken along a line 15-15 in FIG.14;

[0103]FIG. 16 is a partially enlarged plan view showing a part in circleB in FIG. 14;

[0104]FIG. 17 is a cross-sectional view, corresponding to FIG. 15,showing a cross section of a liquid crystal display panel of a ninthembodiment of the invention;

[0105]FIG. 18 is a cross-sectional view, corresponding to FIG. 15,showing a cross section of a liquid crystal display panel of a tenthembodiment of the invention;

[0106]FIG. 19 is a cross-sectional view, corresponding to FIG. 15,showing a cross section of a liquid crystal display panel of an eleventhembodiment of the invention;

[0107]FIG. 20 is a partially enlarged plan view, corresponding to FIG.16, showing a part of a liquid crystal display panel of a twelfthembodiment of the invention;

[0108]FIG. 21 is a partial cross-sectional view showing a part of across section taken along a line 21-21 in FIG. 20 in a verticallyreversed manner;

[0109]FIG. 22 is a cross-sectional view, corresponding to FIG. 15,showing a cross section of a liquid crystal display panel of athirteenth embodiment of the invention;

[0110]FIG. 23 is a cross-sectional view, corresponding to FIG. 15,showing a cross section of a liquid crystal display panel of afourteenth embodiment of the invention;

[0111]FIG. 24 is a perspective view showing the shape of a coveringmember to be provided on the liquid crystal display panel;

[0112]FIG. 25 is a partially enlarged plan view, corresponding to FIG.16, showing a part of a liquid crystal display panel of a fifteenthembodiment of the invention;

[0113]FIG. 26 is a cross-sectional view, corresponding to FIG. 15,showing a cross section of the liquid crystal display panel of thefifteenth embodiment of the invention;

[0114]FIG. 27 is a plan view of a liquid crystal display panel of asixteenth embodiment of the invention;

[0115]FIG. 28 is a cross-sectional view taken along a line 28-28 in FIG.27;

[0116]FIG. 29 is a cross-sectional view, corresponding to FIG. 15,showing a cross section of a liquid crystal display panel of aseventeenth embodiment of the invention;

[0117]FIG. 30 is a cross-sectional view, corresponding to FIG. 15,showing a cross section of a liquid crystal display panel of aneighteenth embodiment of the invention;

[0118]FIG. 31 is a plan view of a liquid crystal display panel of anineteenth embodiment of the invention;

[0119]FIG. 32 is a plan view of a liquid crystal display panel of atwentieth embodiment of the invention;

[0120]FIG. 33 is a cross-sectional view taken along a line 33-33 in FIG.32;

[0121]FIG. 34 is a plan view of a liquid crystal display panel of atwenty-first embodiment of the invention;

[0122]FIG. 35 is a cross-sectional view taken along a line 35-35 in FIG.34;

[0123]FIG. 36 is a cross-sectional view, corresponding to FIG. 35,showing the configuration of a modified example of the liquid crystaldisplay panel of the twenty-first embodiment of the invention;

[0124]FIG. 37 is a plan view of a liquid crystal display panel of atwenty-second embodiment of the invention;

[0125]FIG. 38 is a cross-sectional view, corresponding to FIG. 15,showing a cross section of a first modified example of the liquidcrystal display panel of the invention;

[0126]FIG. 39 is a cross-sectional view, corresponding to FIG. 2,showing a cross section of a second modified example of the liquidcrystal display panel of the invention;

[0127]FIG. 40 is a cross-sectional view, corresponding to FIG. 15,showing a cross section of a third modified example of the liquidcrystal display panel of the invention;

[0128]FIG. 41 is a plan view of a conventional liquid crystal displaypanel;

[0129]FIG. 42 is a cross-sectional view taken along a line 42-42 in FIG.41;

[0130]FIG. 43 is a partially enlarged plan view showing a part in circleC in FIG. 41; and

[0131]FIG. 44 is a cross-sectional view of another conventional liquidcrystal display panel.

BEST MODE FOR CARRYING OUT THE INVENTION

[0132] Embodiments of the invention will be described with reference tothe accompanying drawings to describe the invention in more detail.

[0133] First Embodiment: FIG. 1 to FIG. 3

[0134] First, a first embodiment of a liquid crystal display panel ofthe invention will be described. FIG. 1 is a plan view of the liquidcrystal display panel, FIG. 2 is a cross-sectional view taken along aline 2-2 shown in FIG. 1, and FIG. 3 is a partially enlarged plan viewof a part in circle A in FIG. 1.

[0135] This liquid crystal display panel of the first embodiment is areflective liquid crystal display panel for use in a cellular phone, apersonal digital assistant, a timepiece, and the like. The firstembodiment is characterized in that a thin film insulating layer isprovided as an insulating covering member on and around lead electrodesprovided on a first substrate, on driving integrated circuits (IC) ofthe liquid crystal display panel, on a flexible printed circuit board(FPC), and on a second substrate.

[0136] This liquid crystal display panel is, as shown in FIG. 1, amatrix-type liquid crystal display panel having m stripe firstelectrodes 2 provided on a first substrate 1 with a thickness of 0.5 mmand n stripe second electrodes 7 provided on a second substrate 6 with athickness of 0.5 mm, and a display region 23 constituted of m by n pixelportions 24 being intersections of the first electrodes 2 and the secondelectrodes 7. The first substrate 1 and the second substrate 6 areopposed to each other with a predetermined gap provided therebetweenwith not-shown spacers and are bonded together with a sealant 26 asshown in FIG. 2, and a liquid crystal layer 25 is sealed in the gap andhermetically sealed with a closing member 27 so that hermeticity isensured.

[0137] Further, as shown in FIG. 2, a reflector 16 composed of analuminum film or a silver alloy film is provided on the entire face ofthe second substrate 6, and a color filter which is composed of a red(R) color filter 17, a green (G) color filter 18, and a blue (B) colorfilter 19 is provided on the reflector 16. Thereon, a flatteningprotective film 21 is provided to flatten projections and depressions ofthe color filter and prevent an electrical short circuit between thereflector 16 and the second electrodes 7, and the second electrodes 7are provided on the flattening protective film 21. Furthermore, on thefirst electrodes 2 and on the second electrodes 7, alignment films (notshown) are provided to align liquid crystal molecules in the liquidcrystal layer 25 in predetermined directions.

[0138] On the other hand, on the first substrate 1, a retardation film12 and a polarizing film 11 are provided. The polarizing film 11 is anordinary absorption-type polarizing film having one polarizing axisbeing an absorption axis and the other polarizing axis perpendicularthereto being a transmission axis. As the retardation film 12, otherthan a one layer retardation film, two- or three-layered retardationfilms can also be used to improve the contrast and brightness ofdisplay.

[0139] Note that, in FIG. 1, illustration of the polarizing film 11, theretardation film 12, the reflector 16, the color filters, the flatteningprotective film 21, and connecting electrodes 42 is omitted. Besides, asfor lead electrodes 41, though no numeral is given because it isdifficult to show boundaries between the lead electrodes 41 and thefirst electrodes 2 and between the lead electrodes 41 and the secondelectrodes 7, at least portions outside the sealant 26 of theillustrated electrodes are the lead electrodes 41. This also applies toplan views corresponding to this used for description of the followingembodiments.

[0140] By the way, in this liquid crystal display panel, as shown inFIG. 1, the first substrate 1 is made larger in size than the secondsubstrate 6, and a driving IC 36 for applying driving signals byelectric signals to the first electrodes 2 and driving ICs 35 forapplying driving signals by electric signals to the second electrodes 7are mounted on the first substrate 1. Note that the second substrate 6is made to have a size larger than the display region 23 and not toreach a region where the driving ICs 35 and 36 are provided on the firstsubstrate 1.

[0141] Then, the lead electrodes continued to the first electrodes 2 forconnecting the first electrodes 2 and the driving IC 36 are led out fromthe display region 23 to the outside of the sealant 26. On the leadelectrodes, the driving IC 36 is mounted through an anisotropicconductive film containing conductive particles in a polyimide resin,and the film is heated and compressed to cure, so that the firstelectrodes 2 are connected to the driving IC 36 through the leadelectrodes. Such a mounting method is called the Chip on Glass (COG)method.

[0142] Further, the lead electrodes 41 for connecting the secondelectrodes 7 and the driving ICs 35 are also provided on the firstsubstrate. A portion of the sealant 26 is composed of an anisotropicconductive sealant containing conductive particles in an acrylic resin,and a pressure is applied to the second substrate 6 and the firstsubstrate 1 through the anisotropic conductive sealant, so that thesecond electrodes 7 provided on the second substrate 6 are electricallyconducted through the conductive particles to the lead electrodes 41provided on the first substrate 1. Then, the driving ICs 35 are mountedon the lead electrodes 41 similarly to the case of the above-describeddriving IC 36, so that the second electrodes 7 are connected to thedriving ICs 35 through the lead electrodes 41.

[0143] It should be noted that while the driving ICs 35 and 36 aremounted here separately on two sides of the liquid crystal displaypanel, the lead electrodes may be routed so that all the driving ICs aremounted on one side.

[0144] Further, to apply signals to the driving ICs 35 and 36 from anexternal circuit, an FPC 31 being a flexible connecting board connectedto the driving ICs 35 and 36 is provided through the connectingelectrodes 42 shown in FIG. 2 and FIG. 3. Note that the FPC 31 and thedriving ICs 35 and 36 are connected to the connecting electrodes 42using an anisotropic conductive film.

[0145] Further, as shown in FIG. 1 to FIG. 3, a moisture-impermeablethin film insulating layer 22 made of silicon nitride (SiNx) is formedwith a thickness of 250 nm (nanometer) as the insulating covering memberon and around the lead electrodes 41 to cover at least entire portionsof the lead electrodes 41 outside the sealant 26. Furthermore, the thinfilm insulating layer 22 is similarly formed on the driving ICs 35 and36, on a portion of the FPC 31, between the driving ICs 35 and the FPC31, and on the entire face of the second substrate 6 (the lower face inFIG. 2) opposite to the liquid crystal layer 25.

[0146] More specifically, the thin film insulating layer 22 covers theentire face except for a face of the first substrate 1 (the upper facein FIG. 2) opposite to the liquid crystal layer 25 and side facesthereof, the top of the first polarizing film 11 or the firstretardation film 12, and a portion of the FPC 31. Therefore, it ispossible to prevent moisture from permeating the lead electrodes 41, sothat even when the liquid crystal display panel is operated for a longtime at a high temperature and high humidity, electrolytic corrosion ofthe lead electrodes 41 can be prevented for performance of stabledisplay. In particular, since the thin film insulating layer 22 isprovided to overlap the second substrate 6, the distance from the endportion of the thin film insulating layer 22 to the lead electrodes 41is long so that permeation of moisture from the end portion to the leadelectrodes 41 can also be eliminated. Note that while the thin filminsulating layer 22 is provided on the entire face of the secondsubstrate 6 here, this effect can be exhibited when the thin filminsulating layer 22 is provided to overlap with only a portion of thesecond substrate 6.

[0147] Besides, even a film quality when the film is formed by anatmospheric-pressure chemical vapor deposition (CVD) or anatmospheric-pressure optical CVD is usable as the thin film insulatinglayer 22. To prevent electrolytic corrosion of the lead electrodes 41,however, a dense film is required. A film can be formed dense and low inmoisture permeability by a sputtering or by the CVD method in a vacuumcondition, and thus it is particularly effective to use the film formedby this method. Besides, repetition of processes of film formation,cleaning, and film formation a plurality of times is also particularlyeffective because the repetition can prevent pinhole formation in thefilm.

[0148] The thin film insulating layer 22 is preferably formed at 150° C.or lower. This is to prevent deterioration of the liquid crystal layer25 caused at too high temperatures. To prevent deterioration of thepolarizing film 11 and the FPC 31, the film is preferably formed at atemperature lower than that, and temperatures at 150° C. and lower fallwithin an allowable range.

[0149] Owing to the employment of the above-describe structure, thedriving ICs 35 and 36 and the thin film insulating layer 22 can keephermeticity at a portion where the lead electrodes 41 are provided onthe first substrate 1.

[0150] Note that though a cross-sectional view is not shown inparticular, it is assumed that, on the side where the driving IC 36 isprovided, the lead electrodes 41, the driving IC 36, and so on are alsocovered similarly to the case of the side where the driving ICs 35 areprovided. This also applies to the following respective embodiments.

[0151] Further, while the reflector 16 is provided here to extend as faras the outer periphery of the second substrate 6 to have an outerperiphery aligned with that of the flattening protective film 21, thethin film insulating layer 22 is provided also on the side faces of thesealant 26 and the second substrate 6, so that the outer peripheralportion of the reflector 16 is also provided with the thin filminsulating layer 22 and prevented from coming into contact with externalair. This enables prevention of change in quality and corrosion of thereflector 16 even when an aluminum (including its alloy) film or asilver (including its alloy) film is used as the reflector 16, whichpermits employment of the above-described structure whose steps can besimplified because of nonnecessity of pattern formation of the reflector16.

[0152] Furthermore, the thin film insulating layer 22 can be formed alsoin a small gap of about 5 micrometers (μm) between the first substrate 1and the second substrate 6. Therefore, the thin film insulating layer 22can cover the lead electrodes 41 also at a gap portion 53 being aportion of the space outside the sealant 26, which can prevent the leadelectrodes 41 from coming into contact with external air. Incidentally,to attain this effect sufficiently, the thin film insulating layer 22 ispreferably thinner than the gap between the first substrate 1 and thesecond substrate 6, that is, the thickness of the liquid crystal layer.

[0153] The thin film insulating layer 22 is preferable about 100 nm to500 nm in film thickness because it is formed by the sputtering or filmformation by CVD, and when the film is to be formed particularly thick,it can be made thick to about 1000 nm. However, excellent results couldbe obtained when it was in a range about 200 nm to 500 nm.

[0154] As for the material of the thin film insulating layer 22, thesame effect as the above-described silicon nitride film could beobtained even through use of a single film or laminated films of asilicon oxide film or silicon nitride oxide film similarly containingsilicon which was formed in a vacuum condition. Besides, when a thinfilm insulating layer made of metal oxide such as a tantalum oxide filmor a titanium oxide film was employed, a dense film can be formed at lowtemperatures. Such a thin film insulating layer was suitable for thecase using a substrate or a mounted member which was low in resistanttemperature. Further, it is also adoptable to employ a thin filminsulating layer in which two or more different kinds of insulatingfilms are laminated.

[0155] Here, after the liquid crystal layer 25 remaining on the gapportion 53 is sufficiently cleaned off and the driving ICs 35 and 36 andthe FPC 31 are mounted, an oxygen plasma treatment is performed for aportion where the thin film insulating layer is to be formed to removeremnants and contamination, and then the thin film insulating layer 22is formed. The performance of the oxygen plasma treatment before themounting of the driving ICs 35 and 36 causes the surface of thetransparent conductive film forming the lead electrodes 41 to change inquality (change in oxidation degree), which deteriorates conductingcharacteristics thereof with not shown bumps on the driving ICs 35 and36. After the mounting of the driving ICs 35 and 36, on the other hand,the oxygen plasma treatment is allowable, and organic substances can beefficiently removed. Note that, in place of the oxygen plasma treatment,it is also adoptable to perform a plasma treatment using an inert gassuch as an argon gas, an oxygen gas, a nitrogen gas, or a mixed gas oftwo or more kinds of these gases.

[0156] Further, since the amount of moisture passing through the sealant26 can be reduced by the thin film insulating layer 22 provided also onthe side of the sealant 26 in contact with external air, changes incharacteristics of the liquid crystal layer 25 can be decreased toimprove the display quality.

[0157] Beside, the thin film insulating layer 22 is formed only on aportion of the FPC 31 in this embodiment because a terminal forestablishing connection with an external circuit (not shown) is providedon the second substrate 6 side of the FPC 31. For forming the thin filminsulating layer 22 on a portion of the FPC 31, it is only required thata portion where the thin film insulating layer 22 is not to be formed isin advance covered with a polyimide tape, which is peeled off afterformation of the thin film insulating layer 22. This method is effectivealso in terms of capability of protecting an electrode section forconnecting the FPC 31 to the external circuit in a film forming step ofthe thin film insulating layer 22.

[0158] Second Embodiment: FIG. 4 to FIG. 6

[0159] Next, a second embodiment of the liquid crystal display panel ofthe invention and a modified example thereof will be described. FIG. 4is a cross-sectional view, corresponding to FIG. 2, showing a crosssection of the liquid crystal display panel, FIG. 5 is a partiallyenlarged plan view, corresponding to FIG. 3, showing a part near leadelectrodes of the same enlarged, and FIG. 6 is a cross-sectional view,corresponding to FIG. 4, showing the configuration of the modifiedexample. In these drawings, the same numerals are assigned to portionscorresponding to those in the first embodiment.

[0160] The second embodiment is characterized in that a thin filminsulating layer is provided, as an insulating covering member, on theentire face on a second substrate side (the lower side in FIG. 4) of anFPC, and that an insulating resin is provided on a portion of the thinfilm insulating layer. The liquid crystal display panel of the secondembodiment is the same as that of the first embodiment except for thesepoints and a point that a reflector 16 is pattern-formed with an outershape smaller than that of a second substrate 6, and thus thedescription will be omitted or simplified except for the differentpoints.

[0161] In this liquid crystal display panel, a thin film insulatinglayer 22 is provided, as in the first embodiment, on and around leadelectrodes 41, on a driving integrated circuits 35, on the lower face inFIG. 4 of the second substrate 6, and so on. In addition to this, thethin film insulating layer 22 is provided on the entire face of thesecond substrate 6 side of the FPC 31.

[0162] This can increase the distance from the end portion of the thinfilm insulating layer 22 to the lead electrodes 41 also on the FPC 31side to eliminate more effectively permeation of moisture from the endportion into the lead electrodes 41.

[0163] Further an insulating resin 32 composed of silicon resin isprovided on the thin film insulating layer 22 at a portion correspondingto portions of the lead electrodes 41 outside a sealant 26 andtherearound, the driving ICs 35 and 36, and a portion of the flexibleprinted circuit board 31. An epoxy resin is preferable in terms of thelow moisture permeability but has a large thermal contraction which maydeforms the substrate to change the thickness of a liquid crystal layer25 near the sealant 26, and therefore, a silicon resin having a smallthermal contraction and having elasticity is used here. This insulatingresin 32 serves to prevent flaws on the thin film insulating layer 22and reinforce adhesion of the FPC 31 to a first substrate 1 as well ashas a function of preventing moisture from permeating the electrodessuch as the lead electrodes 41 and the like for prevention ofelectrolytic corrosion.

[0164] Since the insulating resin 32 thus provided can prevent entranceof moisture in cooperation with the thin film insulating layer 22 andprevent damage of the thin film insulating layer 22 to allow itsfunction to be stably exhibited, electrolytic corrosion of the leadelectrodes 41 can be prevented.

[0165] Even such a transparent or a white insulating resin 32 for usehere has an effect in reducing moisture permeability to provide asufficient effect of preventing electrolytic corrosion. Meanwhile, whena black or gray insulating resin is used for this liquid crystal displaypanel, the driving ICs 35 and 36 can be shielded from irradiated lightso that optical malfunction of the driving ICs 35 and 36 can beprevented. When the insulating resin is applied to the FPC 31 and alsoto the front face (the upper side face in FIG. 4) side of the firstsubstrate 1 and the black or gray insulating resin is applied to aportion of the front face of the first substrate 1 corresponding to thedriving ICs 35 and 36, it is possible to prevent more surely opticalmalfunction of the driving ICs 35 and 36 as well as to reduce moisturepermeation from the interface between the first substrate 1 and the FPC31, so that electrolytic corrosion can be prevented more effectively.

[0166] It should be noted that, in this liquid crystal display panel,since the connection between the FPC 31 and an external circuit (notshown) is established on the first substrate 1 side (the upper side inFIG. 4) of the FPC 31, it is preferable to from the thin film insulatinglayer 22 after masking is performed to prevent the thin film insulatinglayer 22 from being formed on a terminal portion provided on thisportion. The thin film insulating layer 22, however, is formed mainly onthe second substrate 6 side here, and thus a very thin layer is formedthrough a flow around onto the first substrate 1 side. Since such alayer could be mechanically broken when the terminal portion was formedof copper and gold and the connection to the external circuit wasestablished through use of a connector, and thermally broken when theconnection was established through use of solder, the connection couldbe established without problem even if masking was not performed.Therefore, when the masking for the formation of the thin filminsulating layer 22 is omitted, the steps can be simplified.

[0167] In the example shown in FIG. 4, the thin film insulating layer 22is formed only on the side lower than the first substrate 1 (the secondsubstrate 6 side) in the drawing. As shown in FIG. 6, when the thin filminsulating layer 22 is formed, at the same time, also on the side facesand the upper side of the first substrate 1 so that the thin filminsulating layer 22 is formed on all the faces of the liquid crystaldisplay panel including on the FPC 31, moisture can be prevented fromentering from any face in contact with external air so that thereliability can further be improved.

[0168] When the thin film insulating layer 22 is formed on the sideupper than the first substrate 1 in the drawing, the film can be formeddirectly on the first substrate 1 or on a polarizing film 11 afterbonding thereof. FIG. 6 shows the latter case. In terms of thereliability of the liquid crystal display panel, the latter case wasbetter. The reason is that the polarizing film 11 having a function ofcutting ultraviolet rays can protect the liquid crystal layer 25 fromultraviolet rays generated during the film formation of the thin filminsulating layer 22.

[0169] Third Embodiment: FIG. 7

[0170] Next, a third embodiment of the liquid crystal display panel ofthe invention will be described. FIG. 7 is a cross-sectional view,corresponding to FIG. 2, showing a cross section of the liquid crystaldisplay panel. In this drawing, the same numerals are assigned toportions corresponding to those in the first or second embodiments.

[0171] The third embodiment is characterized in that a second polarizingfilm is provided on a second substrate and that a thin film insulatinglayer is provided on the polarizing film. The liquid crystal displaypanel of the third embodiment is the same as that of the above-describedsecond embodiment except for these points and a point that the reflector16 is not provided, and thus the description will be omitted orsimplified except for the different points.

[0172] As shown in FIG. 7, this liquid crystal display panel is providedwith no reflector and a second polarizing film 14 on the rear side ofthe second substrate 6 (the lower side in the drawing). As the secondpolarizing film 14 used is either an absorption-type polarizing filmhaving one polarizing axis being a transmission axis and the otherpolarizing axis perpendicular thereto being an absorption axis, or areflection-type polarizing film having one polarizing axis being atransmission axis and the other polarizing axis perpendicular threretobeing a reflection axis. When the panel is used in a transflectiveliquid crystal display device, the use of the reflection-type polarizingfilm can realize bright display.

[0173] A thin film insulating layer 22 is provided, as in the secondembodiment, on and around the lead electrodes 41, on the drivingintegrated circuits 35, on a rear face of the FPC 31, and so on. On asecond substrate 6, however, the thin film insulating layer 22 isprovided not directly but through the second polarizing film 14.

[0174] In such a configuration, the second polarizing film 14 canprotect a liquid crystal layer 25 from ultraviolet rays generated in thestep of forming the thin film insulating layer 22. For this protection,it is of course necessary to form the thin film insulating layer 22after provision of the second polarizing film 14. It is more preferableto carry out the formation after a first polarizing film 11 is alsoprovided. Besides, mixture of an ultraviolet reflecting material or anultraviolet absorbing agent into a sealant 26 enables further reductionin the amount of ultraviolet rays irradiated to the liquid crystal layer25.

[0175] According to such a liquid crystal display panel, the thin filminsulating layer 22 can prevent, as in the above-described embodiments,electrolytic corrosion of the lead electrodes 41 as well asdeterioration of the second polarizing film 14. Further, the secondpolarizing film 14 can prevent deterioration of the liquid crystal layer25 during the formation of the thin film insulating layer 22.

[0176] As a modification of this embodiment, a transflective reflectormay be formed on the second substrate 6. As for the position, thetransflective reflector can be provided between the second substrate 6and the liquid crystal layer 25, between the second substrate 6 and thesecond polarizing film 14, or on the rear side of the second polarizingfilm 14. The maximum effect of this embodiment can be utilized when thetransflective reflector is provided on the rear side of the secondpolarizing film 14. More specifically, the transflective reflector is athin aluminum film or a film with holes (openings) for transmittinglight and is thus corroded by moisture, but the corrosion can beprevented by covering also the transflective reflector with the thinfilm insulating layer 22.

[0177] Moreover, in the case of providing the transflective reflectorbetween the second substrate 6 and the second polarizing film 14, whenthe reflector is provided on the entire face of the second substrate 6for shortening of the steps, the cross section of the transflectivereflector comes into contact with external air, and therefore, in thiscase it is effective to prevent corrosion of the cross section andmoisture permeation into an adhesive layer through use of the thin filminsulating layer 22.

[0178] Fourth Embodiment: FIG. 8

[0179] Next, a fourth embodiment of the liquid crystal display panel ofthe invention will be described. FIG. 8 is a cross-sectional view,corresponding to FIG. 2, showing a cross section of the liquid crystaldisplay panel. In this drawing, the same numerals are assigned toportions corresponding to those in the first to third embodiments.

[0180] This fourth embodiment is the same as the above-described thirdembodiment except for the position where a thin film insulating layer isprovided, and thus the description will be omitted or simplified exceptfor this point.

[0181] In this liquid crystal display panel, a thin film insulatinglayer 22 is provided as in the third embodiment, as shown in FIG. 8, onand around lead electrodes 41 and on driving integrated circuits 35.Meanwhile, the thin film insulating layer 22 is provided only at aportion of the outer peripheral portion on the second polarizing film 14provided on a second substrate 6. Further, also on the rear side (thelower side in the drawing) of an FPC 31, the thin film insulating layer22 is provided only near the outer peripheral portion of a firstsubstrate 1. In the step of forming the thin film insulating layer 22,masking is performed to limit the region where the thin film insulatinglayer 22 is to be formed, so that the thin film insulating layer 22 canbe arranged as described above.

[0182] The reason why the thin film insulating layer 22 is provided onlyon the peripheral portion on the second polarizing film 14 is to preventvariation in film thickness of the thin film insulating layer 22 on thesecond polarizing film 14 or variation in display quality due to peelingoff thereof or the like. The reason why the thin film insulating layer22 is provided only on a portion of the rear side of the FPC 31 is notto provide the thin film insulating layer 22 on a portion of the FPC 31to be bent so that the thin film insulating layer 22 will not peel offfrom the FPC 31 even when the FPC 31 is bent as shown in FIG. 8 forconnection to an external circuit (not shown).

[0183] Therefore, the employment of such a configuration permits thematerial of the thin film insulating layer 22 to be selected for usewith a focus on reduction in moisture permeability into the leadelectrodes 41 without attaching importance to the adhesion to theorganic material in the second polarizing film 14 or the FPC 31 and theuniformity during the film formation, thus enabling formation of thethin film insulating layer 22 with a lower moisture permeability toprevent moisture permeation into the lead electrodes 41.

[0184] Fifth Embodiment: FIG. 9 to FIG. 11

[0185] Next, a fifth embodiment of the liquid crystal display panel ofthe invention will be described. FIG. 9 is a plan view of the liquidcrystal display panel, FIG. 10 is a cross-sectional view taken along aline 10-10 shown in FIG. 9, and FIG. 11 is a cross-sectional view takenalong a line 11-11 shown in FIG. 9. In these drawings, the same numeralsare assigned to portions corresponding to those in the first or secondembodiments.

[0186] The fifth embodiment is characterized in that, in addition to athin film insulating layer on a second substrate side (the lower side inFIG. 10 and FIG. 11) of the panel, a second thin film insulating layeris provided as a second insulating covering member on a first substrateside (the upper side in the same drawings).

[0187] This liquid crystal display panel has almost the sameconfiguration as that of the liquid crystal display panel of the secondembodiment described using FIG. 4 and FIG. 5, but is first differentfrom the liquid crystal display panel of the second embodiment in that adriving IC 36 for applying driving signals to second electrodes 7 ismounted on a second substrate 6 while both the driving ICs 35 and 36 aremounted on the first substrate 1 in the second embodiment. Therefore,the lead electrodes for connecting the second electrodes 7 to thedriving IC 36 are also provided on the second substrate 6. Further, thedriving IC 36 is connected to an FPC 131 for the driving IC 36 throughthe connecting electrodes 42, whose illustration is omitted in FIG. 9,on the second substrate 6.

[0188] Secondly, in this liquid crystal display panel, in addition to athin film insulating layer 22 similarly provided as in the secondembodiment, a second thin film insulating layer 122 is provided on thefirst substrate side of the panel. This second thin film insulatinglayer 122 is formed, as shown in FIG. 9 to FIG. 11, of amoisture-impermeable film made of silicon nitride (SiNx) with athickness of 250 nm (nanometer), on and around lead electrodes 41provided on the second substrate 6 to cover entirely at least portionsof the lead electrodes 41 outside a sealant 26, and further similarlyformed also on the driving IC 36, on the entire face on a firstsubstrate 1 side of the FPC 131, between the driving IC 36 and the FPC131, and on the entire face on the side of the first substrate 1 (theupper side in FIGS. 10 and 11) opposite to a liquid crystal layer 25.

[0189] Then, also on this second thin film insulating layer 122, aninsulating resin 32 composed of silicon resin is provided on a portioncorresponding to portions of the lead electrodes 41 outside the sealant26 and therearound, the driving integrated IC 36, and a portion of theFPC 31.

[0190] When the driving IC is provided also on the second substrate 6 asin this liquid crystal display panel, the lead electrodes 41 on thesecond substrate cannot be covered only with the thin film insulatinglayer 22 provided on the second substrate 6 side, and thus it isimportant to provide the second thin film insulating layer 122 also onthe first substrate 1 side. Such an arrangement enables prevention ofmoisture permeation into the connecting electrodes provided on thesecond substrate 6 and electrolytic corrosion thereof.

[0191] Incidentally, the thin film insulating layer 22 and the secondthin film insulating layer 122 can be provided at the same time. Forexample, the liquid crystal display panel only needs to be rotatedaround an axis of the right-left direction in FIG. 10 during the filmformation of the thin film insulating layer. The thin film insulatinglayer 22 and the second thin film insulating layer 122 can be formed indifferent steps, as a matter of course, but the steps are made simplerwhen they are formed at the same time.

[0192] Besides, while the second thin film insulating layer 122 isformed directly on the first substrate 1 here because if the second thinfilm insulating layer 122 is formed on a polarizing film 11, the secondthin film insulating layer 122 has to be removed when the polarizingfilm 11 needs to be repaired, it is of course possible to provide thesecond thin film insulating layer 122 on the polarizing film 11.

[0193] Sixth Embodiment: FIG. 12

[0194] Next, a sixth embodiment of the liquid crystal display panel ofthe invention will be described. FIG. 12 is a cross-sectional view,corresponding to FIG. 2, showing a cross section of the liquid crystaldisplay panel. In this drawing, the same numerals are assigned toportions corresponding to those in the first or second embodiments.

[0195] The sixth embodiment is characterized in that a second thin filminsulating layer is provided as a second insulating covering member on athin film insulating layer and an insulating resin. The liquid crystaldisplay panel of the sixth embodiment is almost the same as that of thesecond embodiment described using FIG. 4 and FIG. 5 except for thispoint, and thus the description will be omitted or simplified except forthe different point.

[0196] In this liquid crystal display panel, a thin film insulatinglayer 22 and an insulating resin 32 are provided as in the secondembodiment, the insulating resin 32 being provided using acrylic resin.Then, as shown in FIG. 12, a second thin film insulating layer 122 isfurther provided on their entire faces to prevent more fully moisturepermeation. The material, thickness, forming method of the second thinfilm insulating layer 122 can be the same as those of the thin filminsulating layer 22.

[0197] With such an arrangement, three layers, that is, the thin filminsulating layer 22, the insulating resin 32, and the second thin filminsulating layer 122 can fully prevent moisture from permeating intolead electrodes 41. In addition, since two layers of the thin filminsulating layer, that is, the first thin film insulating layer 22 andthe second thin film insulating layer 122 can be formed also on the faceof the sealant 26 in contact with external air, it is also possible toreduce the probability of occurrence of pinholes and the moisturepermeability of the portion covering the sealant 26. Moreover, both thefirst thin film insulating layer 22 and the second thin film insulatinglayer 122 are formed on the entire face on a second substrate 6 side ofthe panel so that masking is not particularly necessary.

[0198] Note that, to prevent the thin film insulating layer from flowingaround onto a polarizing film 11, it is preferable to bond to the liquidcrystal display panel the polarizing film 11 with a protective sheet asa protective film adhered thereto, form the thin film insulating layerin that state, and thereafter peel off the protective sheet duringinspection, during use of the liquid crystal display panel, or the liketo thereby remove the thin film insulating layer on the polarizing film11.

[0199] Besides, as for the connection between the FPC 31 and an externalcircuit (not shown), the thin film insulating layer can easily be brokenby an external force of a connector on the external circuit side or thelike to establish electrical conduction as in the second embodiment.

[0200] Seventh Embodiment: FIG. 13

[0201] Next, a seventh embodiment of the liquid crystal display panel ofthe invention will be described. FIG. 13 is a cross-sectional view,corresponding to FIG. 2, showing a cross section of the liquid crystaldisplay panel. In this drawing, the same numerals are assigned toportions corresponding to those in the first and second embodiments.

[0202] The seventh embodiment is characterized in that a covering memberis provided as a second insulating covering member on an insulatingresin. The liquid crystal display panel of the seventh embodiment isalmost the same as that of the second embodiment described using FIG. 4and FIG. 5 except for this point, and thus the description will beomitted or simplified except for the different point.

[0203] In this liquid crystal display panel, a thin film insulatinglayer 22 and an insulating resin 32 are provided as in the secondembodiment, the insulating resin 32 being provided using acrylic resin.Then, as shown in FIG. 13, a covering member 51 composed of apolyethylene terephthalate (PET) film is provided on the insulatingresin 32 from a position overlapping with a portion of a secondsubstrate 6 to a position overlapping with a portion of an FPC 31. Thethickness of the covering member 51 is preferably about 50 μm to 100 μm.With the thickness of this order, the covering member 51 fits with theirregular shape caused by driving ICs 35 and 36 on a first substrate 1so that the distribution in thickness of the insulating resin 32 can berelaxed, while the covering member 51 has a thickness 100 times that ofthe thin film insulating layer 22 and can be thus made to have a verylow moisture permeability. In addition, the covering member 51 is madeto be hard to flaw.

[0204] Here, the steps of forming the thin film insulating layer 22, theinsulating resin 32, and the covering member 51 are preferably performedas follows. Specifically, after the driving ICs 35 and 36 and the FPC 31are mounted on the liquid crystal display panel, the thin filminsulating layer 22 is first formed. Thereafter, the insulating resin 32is applied, the covering member 51 is mounted thereon, they are fittedto each other by applying a pressure thereto, and then the insulatingresin 32 is cured. In this event, it is more preferable to provide athin film insulating layer for moisture proofing in advance on thecovering member 51 or to subject the covering member 51 to a surfacetreatment for enhancing adhesion thereof to the insulating resin 32.

[0205] Such a configuration can further prevent moisture permeation intolead electrodes 41. Further, though use of the thin film insulatinglayer 22 and the covering member 51 together, even if bubbles form inthe insulating resin 32, a poorly adhered portion of the thin filminsulating layer 22 or the insulating resin 32 occurs at a gap portion53 of the first substrate 1 and the second substrate 6 near a sealant26, or pinholes form in the thin film insulating layer 22, the coveringmember 51 can compensate the degradation in moisture proofing propertycaused by the fact so as to ensure very stable characteristics.

[0206] Eighth Embodiment: FIG. 14 to FIG. 16

[0207] Next, an eighth embodiment of the liquid crystal display panel ofthe invention will be described. FIG. 14 is a plan view of the liquidcrystal display panel, FIG. 15 is a cross-sectional view taken along aline 15-15 shown in FIG. 14, and FIG. 16 is a partially enlarged planview of a part in circle B in FIG. 14. In these drawings, the samenumerals are assigned to portions corresponding to those in the firstand second embodiments.

[0208] The eighth embodiment is characterized in that an insulatingresin is provided on and around lead electrodes provided on a firstsubstrate, and a covering member is provided thereon as an insulatingcovering member. The basic configuration of this liquid crystal displaypanel is the same as that of the second embodiment described using FIG.4 and FIG. 5. Thus, different points will be mainly described, and thedescription on the other points will be omitted or simplified.

[0209] First, in this liquid crystal display panel, unlike the secondembodiment, no thin film insulating layer is provided. Second, as shownin FIG. 14 to FIG. 16, an insulating resin 33 composed of black epoxyresin having a black dye in epoxy resin is provided on and around leadelectrodes 41 to cover at least portions of the lead electrodes 41outside a sealant 26. Further, the insulating resin 33 is similarlyprovided also on driving ICs 35 and 36, on a portion of an FPC 31, andalso between the driving ICs 35 and the FPC 31. Of course, theinsulating resin 33 is provided between the driving ICs 35 and 36 andthe sealant 26.

[0210] Then, on the insulating resin 33 (the lower side in FIG. 15), acovering member 51 which has a base made of polycarbonate (PC) formedwith, at least on the insulating conductive film 33 side of the base, agas barrier layer composed of a silicon oxide film and a titanium oxide,a moisture blocking layer, and a transparent conductive film, isprovided in such a manner to cover at least the portions of the leadelectrodes 41 outside the sealant 26, overlap with the driving ICs 35and 36, the FPC 31, and a portion between the driving ICs 35 and 36 andthe FPC 31, and partially overlap with the outer peripheral portion of asecond substrate 6. In other words, the covering member 51 is providedfrom a position overlapping with a portion of the outer periphery of thesecond substrate 6 to a region overlapping with a portion of the firstsubstrate 1 extending out to the FPC 31 side. Incidentally, while thecovering member 51 is provided separately into a first portion disposedon the side where the driving ICs 35 are provided and a second portiondisposed on the side where the driving IC 36 is provided as shown inFIG. 14, the portions may be integrated.

[0211] Here, as shown in FIG. 14 and FIG. 16, the covering member 51 isprovided to a position where the edge portion thereof overlaps with thesealant 26. When the plate-shaped covering member 51 is provided as inthis liquid crystal display panel, it is preferable to decrease thethickness of the insulating resin 33 by pushing the covering member 51to the panel to locate the covering member 51 close to the secondsubstrate 6 so as to reduce the area of the cross section through whichmoisture permeates from the horizontal direction in FIG. 15. In thisevent, when the covering member 51 is pushed, the panel, especially, thesecond substrate 6 receives stress, but the end portion of the coveringmember 51 overlaps with the sealant 26 as described above so that thestress to the second substrate 6 can be mitigated for prevention ofbreakage of the substrate. Further, it is also possible to prevent achange in thickness of a liquid crystal layer 25 due to deformation ofthe substrates and a decrease in display quality caused by the change.However, only for prevention of electrolytic corrosion, it is not alwaysnecessary to provide the end portion of the covering member 51 at thisposition.

[0212] Usable materials for the covering member 51 include, other thanthe above-described PC, a plastic plate, a glass plate, a metal plate, asubstrate composed of a metal plate provided with an anodic oxide layeras a second insulating covering member, a ceramic plate, or a laminatedbonded member. In particular, ceramic is suitable because of its highstrength and low thermal expansion coefficient. A processible ceramicsuch as MACOL glass (trade name) manufactured by Corning Incorporated ismachinable, and thus it can be used to form into a covering member in acomplicated shape. Besides, a thin film ceramic made by extendingalumina into a foil, or porcelain is preferable because of its highstrength and low thermal expansion coefficient. In the case of glass, aphotosensitive glass substrate manufactured by Corning Incorporated isused to enable processing almost the same as metal working. In the caseof a metal plate for use, it has a high ability of electromagnetic waveshielding and thus can prevent malfunction of the driving IC caused bynoise.

[0213] The covering member 51 is preferably composed of a materialhaving a thermal expansion coefficient equivalent to that of a substrate(the second substrate 6 here) in contact with the covering member 51.Such a configuration can prevent the covering member 51 from peeling offfrom the substrate when it is heated in a curing step of the insulatingresin or the like. For example, the covering member 51, composed of thesame glass as the substrate, is preferable in that it can be made equalin thermal expansion coefficient to the substrate.

[0214] The thickness of the covering member 51 is preferably about 50 μmto 700 μm. The plastic film, however, was preferably about 80 μm to 150μm.

[0215] In this liquid crystal display panel, since the insulating resin33 is provided also at the portion of the space between the firstsubstrate 1 and the second substrate 6 outside the sealant 26, at thisportion, the first substrate 1, the insulating resin 33, the secondsubstrate 6, and the covering member 51 overlap one another as seen fromthe first substrate 1 side. Further, since the insulating resin 33 andthe covering member 51 are provided also on the driving ICs 35 and 36and the FPC 31, they have a portion overlapping with the driving ICs 35and 36 and the FPC 31 as seen from the first substrate 1 side. Further,the insulating resin 33 extends off the outer peripheral portion of thecovering member 51 at a portion on the right on paper in FIG. 15.

[0216] By the way, when such a liquid crystal display panel isfabricated, it is preferable that the driving ICs 35 and 36 and the FPC31 are first mounted on the panel body, then the insulating resin 33 isapplied thereto before the covering member 51 is disposed, andthereafter the insulating resin is cured.

[0217] Such fabrication allows the insulating resin 33 to bond the firstsubstrate 1 and the covering member 51. Moreover, though not shown inFIG. 15, when the covering member 51 is disposed on the insulating resin33 before the cure, a portion of the insulating resin 33 seeps outbetween the second substrate 6 and the covering member 51, so that thesecond substrate 6 and the covering member 51 can also be bondedtogether with the seeping-out insulating resin 33.

[0218] Through employment of the above-described structure, the coveringmember 51 and the insulating resin 33 can keep hermeticity of a portionwhere the lead electrodes 41 are provided to prevent moisture permeationinto the lead electrodes 41. In particular, since the covering member 51is provided to overlap with a portion of the second substrate 6 andbonded with the insulating resin 33, there is no space through whichmoisture passes between the covering member 51 and the second substrate6, and therefore it is possible to eliminate moisture permeation fromthis place toward the lead electrodes 41. This enables prevention ofelectrolytic corrosion of the lead electrodes 41 and performance ofstable display even in operation for a long time at a high temperatureand high humidity.

[0219] Note that since the covering member 51 is provided separatelyinto two portions here as shown in FIG. 14, there is a gap therebetween.However, though the liquid crystal display panel is greatly enlarged inthe vertical direction in the cross-sectional view such as FIG. 15 forconvenience of illustration, it is actually very thin. Thus, when thegap is located at a position apart from the lead electrodes 41 inhorizontal direction, that is, a position overlapping with no leadelectrodes as seen from the first substrate 1 side, even if moistureenters from the gap, the moisture has to permeate through the insulatingresin 33 by a very long distance to reach the lead electrodes 41, ascompared the case when moisture enters from a position directly abovethe lead electrodes 41. Therefore, the covering member 51 only in theaforementioned position is allowable in terms of prevention of moisturepermeation even if it has a slight gap or opening.

[0220] Further, the provision of a slight gap in the covering member 51is preferable in terms of capability of discharging excessive insulatingresin 33 from between the two covering members to decrease the distancebetween the substrate and the covering member 51, and is advantageous interms of capability of removing bubble forming in the insulating resin33 through this gap. It is desirable, however, to locate the position ofthe gap as far as possible from the region where the lead electrodes 41are formed.

[0221] Furthermore, the provision of the covering member 51 facilitatesthick accumulation of the insulating resin 33 so that the moisturepermeability can be decreased accordingly. Moreover, the covering member51 provides a high reliability to prevent moisture permeation because itis not a film formed by application and is large in thickness so thatpinholes seldom form therein.

[0222] Ninth Embodiment: FIG. 17

[0223] Next, a ninth embodiment of the liquid crystal display panel ofthe invention will be described. FIG. 17 is a cross-sectional view,corresponding to FIG. 15, showing a cross section of the liquid crystaldisplay panel. In this drawing, the same numerals are assigned toportions corresponding to those in the eighth embodiment.

[0224] The ninth embodiment is characterized in that a second polarizingfilm is provided on a second substrate. The liquid crystal display panelof the ninth embodiment is almost the same as that of theabove-described eighth embodiment except for this point and a point thatthe reflector 16 is not provided, and thus the description will beomitted or simplified except for the different points.

[0225] As shown in FIG. 17, this liquid crystal display panel isprovided with not a reflector but a second polarizing film 14 on therear side (the lower side in the drawing) of a second substrate 6. Then,a covering member 51 and the second polarizing film 14 are disposed witha predetermined gap provided therebetween on the second substrate 6.

[0226] As the second polarizing film 14, both an absorption-typepolarizing film and a reflection-type polarizing film are usable.Besides, a scattering layer and a reflector may be provided togetherwith the second polarizing film 14 so that a combined layer composed ofthese may be formed on the rear side of the second substrate 6.

[0227] The gap provided between the covering member 51 and the secondpolarizing film 14 as in this embodiment can prevent an insulating resin33 bonding the covering member 51 from leaking from between the coveringmember 51 and the second substrate 6 and contaminating the secondpolarizing film 14. When RDF-C (trade name) manufactured by 3M being areflection-type polarizing film is used as the second polarizing film14, this polarizing film is made by laminating layers different inrefractive index into many layers, and thus the layers peel off fromeach other due to an external force exerted on the cross section of thesecond polarizing film 14, resulting in distortion of polarizationproperty thereof. However, a slight gap, which is provided between thesecond polarizing film 14 and the covering member 51, can prevent anexternal force from the covering member 51 from being exerted on thesecond polarizing film 14 and is thus effective in improving thereliability of the second polarizing film 14 and in preventing adecrease in display quality.

[0228] Tenth Embodiment: FIG. 18

[0229] Next, a tenth embodiment of the liquid crystal display panel ofthe invention will be described. FIG. 18 is a cross-sectional view,corresponding to FIG. 15, showing a cross section of the liquid crystaldisplay panel. In this drawing, the same numerals are assigned toportions corresponding to those in the eighth and ninth embodiments.

[0230] The tenth embodiment is characterized in that a second polarizingfilm provided on a second substrate is used also as an insulatingcovering member. The liquid crystal display panel of the tenthembodiment is the same as that of the above-described ninth embodimentexcept for this point, and thus the description will be omitted orsimplified except for the different point.

[0231] As shown in FIG. 18, in this liquid crystal display panel, noindependent covering member 51 is provided, and, instead of this, apolarizing film having a size reaching the position where a coveringmember is to be provided is used as a second polarizing film 14 providedon the rear side of a second substrate 6, and is used also as theinsulating covering member. Incidentally, the second substrate 6 and thesecond polarizing film 14 are bonded together with an adhesive layer.Further, the second polarizing film 14 is not separated between the sidewhere driving ICs 35 are provided and the side where a driving IC 36 isprovided, but shall be used as an integrated covering member.

[0232] This configuration eliminates such a mutual positionalinterference problem that the second polarizing film 14 overlaps withthe covering member 51 or that the covering member 51 extends into thedisplay region, so that even when lead electrodes 41 are covered, thedisplay region can occupy a wide area as close as possible to the endportion of the second substrate 6. In addition, there is no need toseparately bond the second polarizing film 14 and the covering member,so that the fabrication process can be shortened.

[0233] To increase the reliability at a high temperature and highhumidity, it is also adoptable to employ a method in which the adhesivelayer for use in bonding the second polarizing film 14 and the secondsubstrate 6 is not provided at a portion corresponding to the leadelectrodes 41, and in stead, at this portion, the second polarizing film14 and the second substrate 6 are bonded together with an insulatingresin 33 seeping out between them.

[0234] Further, formation of a gas barrier layer and a moisture blockinglayer on the second polarizing film 14 at the portion corresponding tothe lead electrodes 41 can provide a structure more suitable forprevention of electrolytic corrosion of lead electrodes 41.

[0235] When the display region exists close to the substrate end faceson the driving ICs 35 and 36 sides of the second substrate 6, atransparent optical isotropic material is used as the insulating resin33, so that even if the insulating resin 33 extends off to the displayregion side, the resin can be prevented from affecting the displayquality.

[0236] As described above, the second polarizing film 14 provided on thelower side of the second substrate 6 is used also as the coveringmember, which makes it possible to prevent electrolytic corrosion of thelead electrodes 41 as well as to increase the display region and reducethe weight and thickness, resulting in a liquid crystal display panelwith excellent reliability and display quality. Moreover, when ascattering layer and a reflector are provided together with the secondpolarizing film 14 to form a combined layer of these on the rear side ofthe second substrate 6, or when a polarizing film which has a multiplelayer structure such as RDF-C (trade name) is used, the moisturepermeability of the second polarizing film 14 can further be reduced,resulting in a further enhanced effect in preventing electrolyticcorrosion of the lead electrodes 41.

[0237] Eleventh Embodiment: FIG. 19

[0238] Next, an eleventh embodiment of the liquid crystal display panelof the invention will be described. FIG. 19 is a cross-sectional view,corresponding to FIG. 15, showing a cross section of the liquid crystaldisplay panel. In this drawing, the same numerals are assigned toportions corresponding to those in the eighth and ninth embodiments.

[0239] The eleventh embodiment is a developed form of theabove-described tenth embodiment and is characterized in that a secondpolarizing film provided on a second substrate is used also as aninsulating covering member, that a covering member is further providedas a second insulating covering member on the second polarizing film,and that a second insulating resin is provided on lead electrodes. Theliquid crystal display panel of the eleventh embodiment is the same asthat of the above described tenth embodiment except for these points,and thus the description will be omitted or simplified except for thedifferent points.

[0240] In this liquid crystal display panel, as shown in FIG, 19, apolarizing film having a size reaching the position where a coveringmember is to be provided is used as a second polarizing film 14 providedon the rear side of a second substrate 6, and is used also as theinsulating covering member, and further a covering member 51 is providedon the second polarizing film 14 at a position corresponding to those inthe cases of the eighth and ninth embodiments. The covering member 51may be provided either separately or integrally between the side wheredriving ICs 35 are provided and the side where a driving IC 36 isprovided, and integrally provided.

[0241] When the covering member 51 is provided on the second polarizingfilm 14 as described above, the covering member 51 is provided on analmost flat face, so that the covering member 51 can be bonded to beflat with high accuracy of position using an adhesive layer. As a matterof course, an insulating resin 33 never seeps into the display regionwhen the covering member 51 is bonded.

[0242] Further, in this liquid crystal display panel, a secondinsulating resin 34 having a viscosity lower than that of the insulatingresin 33 is provided on and around a portion of the lead electrodes 41between the driving ICs 35 and 36 and a sealant 26, so as to provide twokinds of insulating resins, that is, the insulating resin 33 and thesecond insulating resin 34.

[0243] It can be reasoned that the insulating resin 33 cannot be appliedwell to the portion between the driving ICs 35 and 36 and the sealant26, in particular, a portion of the space between the first substrate 1and the second substrate 6 outside the sealant 26 because it is narrow,and thus the second insulating resin 34 having a lower viscosity is usedto enable the application also to the narrow space with ease andreliability. The second insulating resin 34 may be cured before theapplication of the insulating resin 33 or at the same time with thecuring step of the insulating resin 33.

[0244] Besides, when the driving ICs 35 and 36 are mounted on the leadelectrodes 41 by the COG method and are left standing thereafter for along time until installation of the FPC 31 and the covering member 51,it is also effective to use a resin capable of curing in a short time asthe second insulating resin 34 and apply it on lead electrodes 41 formoisture blocking to some degree.

[0245] In any case, the two layers of the covering members and the twolayers of the insulating resins can surely prevent moisture permeationinto the lead electrodes 41 for prevention of electrolytic corrosionthereof.

[0246] Twelfth Embodiment: FIG. 20 and FIG. 21

[0247] Next, a twelfth embodiment of the liquid crystal display panel ofthe invention will be described. FIG. 20 is a partially enlarged planview, corresponding to FIG. 16, showing a part of the liquid crystaldisplay panel, and FIG. 21 is a partial cross-sectional view showing ina vertically reversed manner a part of the cross section taken along aline 21-21 in FIG. 20. In these drawings, the same numerals are assignedto portions corresponding to those in the eighth embodiment.

[0248] The twelfth embodiment is characterized in that a first coveringmember in a flat-plate shape and a second covering member having aU-shaped cross section are provided as an insulating covering member.The liquid crystal display panel of the twelfth embodiment is the sameas that of the eighth embodiment described using FIG. 14 to FIG. 16except for this point, and thus the description will be omitted orsimplified except for the different point.

[0249] In this liquid crystal display panel, as shown in FIG. 20 andFIG. 21, a first covering member 29 and a second covering member 30 areprovided as the insulating covering member to be provided on aninsulating resin 33. Among them, the first covering member 29 is similarto the covering member 51 in the eighth embodiment, and has a flatshape. The position of the first covering member 29 to be provided isalmost similar thereto, but in order not to overlap with the secondcovering member 30, the first covering member 29 is provided only withina position somewhat apart from the end portion of a first substrate 1,on the side where the second covering member 30 is provided.

[0250] On the other hand, at the end portion of the first substrate 1 onthe right in FIG. 20, the second covering member 30 having a U-shapedcross section is provided as shown in FIG. 21. The material andthickness of the second covering member 30 are the same as those of thefirst covering member 29. While only the first substrate 1 is seen inthe cross section in FIG. 21, this second covering member 30 is providedto have the first substrate 1 and a second substrate 6 fitted inside theletter U. An insulating resin gap portion 67 for exhausting bubbles inthe insulating resin 33 and allowing an excessive insulating resin 33 toflow out to the outside, is provided between the second covering member30 and the first insulating covering member 29.

[0251] Then, the second covering member 30 is bonded to the firstsubstrate 1 with the insulating resin 33. Further, the insulating resin33 slightly flows around onto the side opposite to the side wheredriving ICs 35 are provided, and the similar flowing around occurs alsoon the second substrate 6, so that the second covering member 30 is alsobonded to the second substrate 6.

[0252] It should be noted that numeral 63 in FIG. 21 denotes a polyimideresin constituting the anisotropic conductive film for use in connectinglead electrodes 41 and the driving ICs 35, and numeral 64 denotes aconductive particle contained therein.

[0253] In this liquid crystal display panel, the second covering member30 provided as described above can prevent the insulating resin 33 fromhanging down from the end portion of the first substrate 1. In addition,the first covering member 29 and the second covering member 30 can applya pressure to the insulating resin 33, so that the insulating resin 33can efficiently be applied also to a narrow gap portion 53 between thefirst substrate 1 and the second substrate 6 near a sealant 26. In thisevent, the excessive insulating resin 33 pushed out by this applicationof pressure can escape to the insulating resin gap portion 67, and aflowing around portion 52 and an extending portion 55 along the sealant26.

[0254] Therefore, the provision of the first covering member 29 and thesecond covering member 30 as described above greatly improves theapplication property of the insulating resin 33 to the gap between thefirst substrate 1 and the second substrate 6 near the sealant 26 andallows the bubble forming during the cure of the insulating resin andthe excessive insulating resin to escape, so that the hermeticity forthe lead electrodes 41 can easily be improved to greatly reduce themoisture permeability into the lead electrodes 41.

[0255] Thirteenth Embodiment: FIG. 22

[0256] Next, a thirteenth embodiment of the liquid crystal display panelof the invention will be described. FIG. 22 is a cross-sectional view,corresponding to FIG. 15, showing a cross section of the liquid crystaldisplay panel. In this drawing, the same numerals are assigned toportions corresponding to those in the eighth embodiment.

[0257] The thirteenth embodiment is characterized in that an insulatingresin is provided on both sides of an FPC. The liquid crystal displaypanel of the thirteenth embodiment is almost the same as that of theeighth embodiment described using FIG. 14 to FIG. 16 except for thispoint, and thus the description will be omitted or simplified except forthe different point.

[0258] As shown in FIG. 22, also in this liquid crystal display panel,while the insulating resin is provided at a position similar to that inthe case of the eighth embodiment, it is provided on an FPC 31 at aslightly larger portion.

[0259] As the resin, a transparent ultraviolet curing epoxy resin orultraviolet curing acrylic resin is used to form an insulating resin 32.The ultraviolet curing resin can cure in a short time, and thus its usecan prevent a covering member 51 from moving during the cure.

[0260] Further, an FPC insulating resin 49 is provided also on a firstsubstrate 1 side (the upper side in FIG. 22) of the FPC 31. As thisresin, it is preferable to use the same resin as the insulating resin 32when giving propriety to mechanical strength. In other words, elasticresin as represented by a silicon resin is sometimes weak in adhesion tothe FPC, and thus an epoxy resin or an acrylic resin is preferable toattain its mechanical strength.

[0261] The FPC insulating resin 49 provided as described above canprevent moisture from entering from the outer periphery side of thepanel not to only lead electrodes 41 but also to connecting electrodes42 connected to the FPC 31, and prevent electrolytic corrosion thereof.

[0262] Fourteenth Embodiment: FIG. 23 and FIG. 24

[0263] Next, a fourteenth embodiment of the liquid crystal display panelof the invention will be described. FIG. 23 is a cross-sectional view,corresponding to FIG. 15, showing a cross section of the liquid crystaldisplay panel, and FIG. 24 is a perspective view showing the shape of acovering member to be provided on this liquid crystal display panel. Inthese drawings, the same numerals are assigned to portions correspondingto those in the eighth embodiment.

[0264] The fourteenth embodiment is a developed form of theabove-described twelfth embodiment, and is characterized in that thecovering member in a shape shown in FIG. 24 is used. The liquid crystaldisplay panel of the fourteenth embodiment is the same as that of theabove-described twelfth embodiment except for this point, and thus thedescription will be omitted or simplified except for the differentpoint. Incidentally, in FIG. 24, the covering member is shown with thestate thereof in FIG. 23 being vertically reversed.

[0265] A covering member 151 for use in this liquid crystal displaypanel has, as shown in FIG. 23 and FIG. 24, a shape covering the endportions of a first substrate 1 and a second substrate 6 on the sidewhere lead electrodes 41 led out. The cross section has a shape of theletter U. Further, on the side where an FPC 31 is provided, an FPC slit57 is provided to take the FPC 31 out of the covering member 151, andfurthermore, an FPC slit flange 59 is provided to prevent an insulatingresin 33 from greatly extending off to the outside from the FPC slit 57.Moreover, the covering member 151 is provided with introducing holes 58as openings for introducing the insulating resin. The introducing holes58 are preferably provided at portions where they do not overlap withlead electrodes 41 or connecting electrodes 42 as seen from the firstsubstrate 1 side. Such an arrangement can reduce to a minimum influencedue to nonexistence of the covering member at the introducing holes 58.

[0266] Besides, although the inside of the covering member 151 is notillustrated in FIG. 24, this covering member 151 may be transparent. Thetransparent covering member 151 is preferable because of easy check ofthe application state of the insulating resin 33 and the occurrencestate of bubbles, while the covering member is preferably black having alight shielding effect in order to shield driving ICs 35 and 36 fromlight. Therefore, the covering member 151 preferably has a transparentface on the side where the lead electrodes are provided and a black faceon the side opposite thereto with the driving ICs 35 and 36 and thefirst substrate 1 intervening therebetween.

[0267] Such a covering member 151 is installed before the application ofthe insulating resin 33 to have the first substrate 1 and the secondsubstrate 6 fitted inside the letter U of the cross section as shown inFIG. 23. In this event, the covering member 151 shall be fitted deepenough for the side face of the first substrate 1 to come into contactwith the covering member 151. Thereafter, the insulating resin 33 isfilled through the introducing holes 58. In this event, an excessiveinsulating resin 33 is partially discharged from the FPC slit 57 andalso from the introducing holes 58 not in use for introduction of theinsulating resin 33. Thereafter, bubbles forming when the insulatingresin 33 cures can be exhausted similarly. Then, the insulating resin 33forms into a state slightly swelling out from the introducing holes 58.

[0268] It should be noted that, in the example shown in FIG. 24, theside face of the covering member 151 is provided with a substrate groove60 into which the first substrate 1 is fitted so that the side face ofthe covering member 151 is located inside the end portion of the firstsubstrate 1. Such a configuration enables the excessive insulating resin33 and the bubbles to be exhausted also through the substrate groove 60.Of course, it is not necessary to provide the substrate groove 60 whenthe position of the side face of the covering member 151 is locatedoutside the end portion of the first substrate 1, and it is necessary toprovide a substrate groove into which the second substrate 6 is fittedwhen the position is located inside the end portion of the secondsubstrate 6.

[0269] In the case of using such a covering member 151, the coveringmember 151 which continues from the upper side to the lower side of thefirst substrate 1 is to be provided, so that even when a contractionstress or an expansion stress occurs in the cure of the insulating resin33, the stress never concentrates on one face, leading to prevention ofwarpage of the substrate. Further, since the covering member 151 is incontact with both the first substrate 1 and the second substrate 6, thecovering member 151 can reinforce the substrates.

[0270] Moreover, also a face perpendicular to the first substrate 1 ofthe covering member 151 is in contact with the insulating resin 33 toblock external air so that the hermeticity at the lead electrodes 41becomes fully secured. This provides a structure very effective inpreventing electrolytic corrosion.

[0271] Fifteenth Embodiment: FIG. 25 and FIG. 26

[0272] Next, a fifteenth embodiment of the liquid crystal display panelof the invention will be described. FIG. 25 is a partially enlarged planview, corresponding to FIG. 16, showing a part of the liquid crystaldisplay panel, and FIG. 26 is a cross-sectional view, corresponding toFIG. 15, showing a cross section of this liquid crystal display panel.In these drawings, the same numerals are assigned to portionscorresponding to those in the eighth embodiment.

[0273] The fifteenth embodiment is characterized in that when the gapbetween substrates is narrow, and thus an insulating resin 33 cannotsufficiently be applied thereto, the space of the gap is filled with asecond insulating resin having a low viscosity. The liquid crystaldisplay panel of the fifteenth embodiment is almost the same as that ofthe above-described eighth embodiment described using FIG. 14 to FIG. 16except for this point, and thus the description will be omitted orsimplified except for the different point.

[0274] In this liquid crystal display panel, a ferroelectric liquidcrystal is employed for a liquid crystal layer 25 and thus a thicknessthereof is about 1 μm, and accordingly the gap between a first substrate1 and a second substrate 6 is just at that level. As a result of theexperiments conducted by the inventors, it was verified that in theaforementioned case, unless a resin for use has a very low viscosity, aninsulating resin does not sometimes flow into a space between the firstsubstrate 1 and the second substrate 6. When the insulating resin havinga low viscosity is used, however, it flows away during its applicationand cannot be accumulated high enough to reach a covering member 51 whenapplied to a large area. On the other hand, the resin used as aninsulating resin 33 in the eighth embodiment and so on is very hard tofill the narrow space having a thickness of 1 μm.

[0275] Hence, with the knowledge of impossibility of sufficientlyfilling into the space between the first substrate 1 and the secondsubstrate 6, the insulating resin 33 used in the eighth embodiment andso on is first applied, and the covering member 51 is disposed. Then, aspace portion 39 which cannot be filled with the insulating resin 33 asshown in FIG. 25 is created, and thereafter a second insulating resin 34having a viscosity lower than that of the insulating resin 33 isintroduced from near the end portion of the covering member 51 to sealthe space portion 39. The second insulating resin 34 having a lowviscosity can be introduced into the space portion 39 with ease bycapillarity and can cover lead electrodes 41 to prevent moisturepermeation thereinto.

[0276] Note that even if the space portion 39 cannot completely befilled with the second insulating resin 34 as shown in FIG. 25, theeffect of preventing moisture permeation can be attained by sealing thespace portion 39 with the second insulating resin 34 to shield it fromthe external air.

[0277] Further, in this liquid crystal display panel, since driving ICs35 having a large height are used as shown in FIG. 26, the driving ICs35 extend downward lower than the second substrate 6 in the drawing. Theinsulating resin 33 is provided, the covering member 51 is disposedthereon, and thereafter the insulating resin 33 is thermally cured. Inthis time, the insulating resin 33 thermally contracts. When thecovering member 51 is pulled to the first substrate 1 side due to thisthermal contraction, the covering member 51 is stuck on the driving ICs35. Therefore, it is preferable to use as the covering member 51 aflexible material capable of deforming in accordance with the shape ofthe driving ICs 35 in the above-mentioned case to keep in close contactwith the insulating resin 33.

[0278] Sixteenth Embodiment: FIG. 27 and FIG. 28

[0279] Next, a sixteenth embodiment of the liquid crystal display panelof the invention will be described. FIG. 27 is a plan view of the liquidcrystal display panel, and FIG. 28 is a cross-sectional view taken alonga line 28-28 shown in FIG. 27. In these drawings, the same numerals areassigned to portions corresponding to those in the eighth embodiment.

[0280] The sixteenth embodiment is characterized in that a coveringmember is composed of a black member and is used as a panel cover of theliquid crystal display panel. This liquid crystal display panel, inwhich the vertical relation between a first substrate and a secondsubstrate is reversed, looks greatly different from that of the eighthembodiment but has many points in basic configuration common therewith,and thus the description on the common points will be omitted orsimplified.

[0281] In this liquid crystal display panel, since a covering member 101is used as the panel cover, the upper side in FIG. 28 is the visibleside, on which a second substrate 6 is disposed, and a first substrate 1is disposed on the side opposite thereto. Then, a reflector 16 andrespective color filters 17, 18, and 19, and a flattening protectivefilm 21 are disposed on a liquid crystal layer 25 side of the firstsubstrate 1, and a polarizing film 11 and a retardation film 12 aredisposed on the visible side of the second substrate 6. However, leadelectrodes 41, driving ICs 35 and 36, and an FPC 31 are provided on theface on the liquid crystal layer 25 side of the first substrate 1 as inthe eighth embodiment.

[0282] Then, also in this liquid crystal display panel, an insulatingresin 33 composed of the black epoxy resin having the black dye in theepoxy resin is provided in a region including the top of the leadelectrodes 41 and therearound, the top of the driving ICs 35 and 36, anda portion of the top of the FPC 31 as in the eighth embodiment.

[0283] On the insulating resin 33, the covering member 101 is providedas the insulating covering member, and this covering member 101 isformed by kneading a resin with a black dye, processing them into asheet shape, and stamping the sheet by a press into an outer contour andinner contour of the covering member 101. This covering member 101 isdisposed on the polarizing film 11 provided on the second substrate 6 asshown in FIG. 28, and is provided not only on the side where theinsulating resin 33 is provided but around the entire periphery of thesecond substrate 6 as shown in FIG. 27, so that the covering member 101is used as a panel cover for shielding the outside of a display region23 to clarify the display region 23.

[0284] This covering member 101 is bonded, as in the eighth embodiment,to the first substrate 1 and the second substrate 6 (actually to thepolarizing film 11 thereon) with the insulating resin 33. A small amountof the insulating resin 33 is provided on the second substrate 6 also onsides where no driving ICs 35 and 36 are provided, so that the coveringmember 101 and the second substrate 6 are bonded together also at theseportions.

[0285] Such a configuration can not only provide the effect ofpreventing electrolytic corrosion equivalent to that of the eighthembodiment, but also reduce the number of parts and the number of stepsbecause there is no need to provide a separate panel cover. Further, theinsulating resin 33 is provided on the entire outer peripheral portionof the polarizing film 11 and thus can prevent moisture permeation intothe polarizing film 11 to improve the reliability of the polarizing film11 as well. Incidentally, it is also conceivable to use a transparentcovering member and apply the insulating resin 33 on the outside of thedisplay region by an inkjet method or a printing method to form a panelcover. The use of the black covering member 101, however, can providemore easily a high positional accuracy.

[0286] Seventeenth Embodiment: FIG. 29

[0287] Next, a seventeenth embodiment of the liquid crystal displaypanel of the invention will be described. FIG. 29 is a cross-sectionalview, corresponding to FIG. 15, showing a cross section of the liquidcrystal display panel. In this drawing, the same numerals are assignedto portions corresponding to those in the eighth embodiment.

[0288] The seventeenth embodiment is characterized in that a portion ofan FPC is used as an insulating covering member. The liquid crystaldisplay panel of the seventeenth embodiment is the same as that of theeighth embodiment described using FIG. 14 to FIG. 16 except for thispoint, and thus the description will be omitted or simplified except forthe different point.

[0289] In this liquid crystal display panel, as shown in FIG. 29, nocovering member is provided on an insulating resin 33. Then, as the FPCto be connected to a connecting electrode 42, an FPC 102 which has afree end portion 103 beyond a connecting terminal with the connectingelectrode 42 is used. The free end portion 103 is disposed on theinsulating resin 33 in close contact therewith, and a portion thereof ismade to overlap with and fix on a second substrate 6, so that the freeend portion 103 is used as the insulating covering member. The free endportion 103 of the FPC 102 and the second substrate 6 may be bondedtogether with an adhesive or with the insulating resin 33 which iscaused to seep into the space between the free end portion 103 and thesecond substrate 6.

[0290] Even such a configuration can decrease the moisture permeabilityinto a lead electrode 41 to prevent electrolytic corrosion.

[0291] Eighteenth Embodiment: FIG. 30

[0292] Next, an eighteenth embodiment of the liquid crystal displaypanel of the invention will be described. FIG. 30 is a cross-sectionalview, corresponding to FIG. 15, showing a cross section of the liquidcrystal display panel. In this drawing, the same numerals are assignedto portions corresponding to those in the eighth embodiment.

[0293] The eighteenth embodiment is characterized in that a thin filminsulating layer is further provided as a second insulating coveringmember on a covering member. The liquid crystal display panel of theeighteenth embodiment is the same as that of the above-described eighthembodiment except for this point, and thus the description will beomitted or simplified except for the different point.

[0294] In this liquid crystal display panel, as shown in FIG. 30, aninsulating thin film 22 is provided on an FPC 31, an insulating resin33, a covering member 51, and a second substrate 6 to cover thesemembers. The material, thickness, and forming method thereof are thesame those in the first embodiment.

[0295] With such a configuration, three members, that is, the thin filminsulating layer 22, the covering member 51, and the insulating resin 33can prevent moisture permeation into a lead electrode 41 to preventoccurrence of electrolytic corrosion very fully. In particular, when thecovering member 51 is provided with a gap or opening, such aconfiguration exhibits a great effect.

[0296] Nineteenth Embodiment: FIG. 31

[0297] Next, a nineteenth embodiment of the liquid crystal display panelof the invention will be described. FIG. 31 is a plan view of the liquidcrystal display panel. In this drawing, the same numerals are assignedto portions corresponding to those in the eighth embodiment.

[0298] The nineteenth embodiment is characterized in that a portionoverlapping with driving ICs of the covering member is colored in black.The liquid crystal display panel of the nineteenth embodiment is almostthe same as that of the above-described eighth embodiment except forthis point, and thus the description will be omitted or simplifiedexcept for the different point.

[0299] In this liquid crystal display panel, as shown in FIG. 31, atransparent insulating resin 32 is provided, and portions overlappingwith driving ICs 35 and 36, as seen from a first substrate 1 side, of acovering member 51 are made colored portions 71 which are colored inblack to absorb light within an ultraviolet wave range and a visiblelight wave range. Specifically, the covering member 51 is composed of aplastic film, and the portions to become the colored portions 71 areimpregnated with a black pigment.

[0300] The colored portions 71 provided in the covering member 51 asdescribed above can shield the driving ICs 35 and 36 from light andprevent the ICs from malfunctioning due to light. Further, it is alsopossible to align the covering member 51 to the panel with ease with thecolored portions 71 as a guide.

[0301] Incidentally, in this liquid crystal display panel, since it isimpossible to irradiate ultraviolet rays to the insulating resin 32 at aportion covered with the colored portions 71, a thermosetting resin issuitable for use as the insulating resin 32.

[0302] Further, it is preferable to form a light blocking portion byapplying the insulating resin 33 or the like also onto a portioncorresponding to the driving ICs 35 and 36 on the face of the firstsubstrate 1 opposite to the side where the driving ICs 35 and 36 areprovided. In such a configuration, light to the driving ICs 35 and 36can be blocked by both faces, which is more effective in preventing theICs from malfunctioning.

[0303] Twentieth Embodiment: FIG. 32 and FIG. 33

[0304] Next, a twentieth embodiment of the liquid crystal display panelof the invention will be described. FIG. 32 is a plan view of the liquidcrystal display panel, and FIG. 33 is a cross-sectional view taken alonga line 33-33 shown in FIG. 32. In these drawings, the same numerals areassigned to portions corresponding to those in the eighth embodiment.

[0305] The twentieth embodiment is characterized in that outerperipheral walls are provided for preventing an insulating resin fromflowing out. The liquid crystal display panel of the twentiethembodiment is also almost the same as that of the above-described eighthembodiment except for this point, and thus the description will beomitted or simplified except for the different point.

[0306] In this liquid crystal display panel, as shown in FIG. 32 andFIG. 33, outer peripheral walls 73 are provided on a first substrate 1.The outer peripheral walls 73 are made of resin and bonded to the firstsubstrate 1 with outer peripheral wall adhesive layers 74 made of anepoxy resin or a double-sided tape. The positions for providing theouter peripheral walls 73 are located at the outer peripheral portion ofthe region where an insulating resin 33 is provided. Here, theinsulating resin 33 is provided separately into a portion to cover leadelectrodes 41 connected to driving ICs 35 and a portion to cover thelead electrodes 41 connected to a driving IC 36.

[0307] For fabricating this liquid crystal display panel, it ispreferable that after the driving ICs 35 and 36 and an FPC 31 aremounted on the liquid crystal display panel body, the outer peripheralwalls 73 are fixed on the first substrate 1 with the outer peripheralwall adhesive layers 74, and thereafter the insulating resin 33 isapplied to a necessary portion. In this event, it is preferable that theresin is caused to somewhat overflow from the outer peripheral walls 73in order to remove bubbles from the gap between the first substrate 1and a second substrate 6 and near the driving ICs 35 and 36. Thereafter,a covering member 51 is disposed on the insulating resin 33, a pressureis applied thereto, and a heat treatment is performed for curing theresin, so that this liquid crystal display panel is completed.

[0308] The outer peripheral walls 73 provided as described above canprevent the resin from flowing out into an unintended portion in a stepof applying the insulating resin 33, and from hanging down or extendingoff the outer periphery of the first substrate 1. Further, the provisionof the outer peripheral walls 73 also enables the resin to fluently flowat the outer peripheral portion of the second substrate 6.

[0309] Incidentally, the outer peripheral walls 73 are preferablyprovided up to a height to come into contact with the covering member 51as shown in FIG. 33. Besides, FIG. 32 shows an example in which threerectangular parallelepiped members and one L-shaped member are providedas the outer peripheral walls 73, but the number and the shape of theouter peripheral walls are not limited to these. Further, the outerperipheral walls 73 may be formed directly on the first substrate 1 by adispenser.

[0310] Twenty-First Embodiment: FIG. 34 to FIG. 36

[0311] Next, a twenty-first embodiment of the liquid crystal displaypanel of the invention and a modified example thereof will be described.FIG. 34 is a plan view of the liquid crystal display panel, FIG. 35 is across-sectional view taken along a line 35-35 shown in FIG. 34, and FIG.36 is a cross-sectional view, corresponding to FIG. 35, showing theconfiguration of the modified example. In these drawings, the samenumerals are assigned to portions corresponding to those in the eighthembodiment.

[0312] The twenty-first embodiment is characterized in that openings areprovided in a covering member. The liquid crystal display panel of thetwenty-first embodiment is also almost the same as that of theabove-described eighth embodiment except for this point, and thus thedescription will be omitted or simplified except for the differentpoint.

[0313] In this liquid crystal display panel, as shown in FIG. 34, acovering member 51 is provided with a plurality of openings 79. Theseopenings 79 are, as shown in FIG. 35, for exhausting an excessive resinand bubbles 80 in application of an insulating resin 33. When providingsmall openings 79 near the end portion of a second substrate 6 and largeopenings 79 at a portion apart from the end portion, exhaustion ofbubbles could be facilitated.

[0314] The openings 79 are provided as described above to exhaust thebubble and excessive resin for improved adhesion between the insulatingresin 33 and the covering member 51 and prevention of occurrence ofpinholes in the insulating resin 33, so that moisture permeation intothe lead electrodes 41 can be effectively prevented.

[0315] Incidentally, when the openings 79 are provided, the insulatingresin 33 can be prevented from greatly extending to the outside of theopenings 79. This is because a portion of the insulating resin 33 flowsout with the bubbles 80 from the openings 79, and progress of theinsulating resin 33 stops near the openings 79. The resin flowing out inthis event only needs to be wiped off before cure or cut away after thecure. Therefore, the openings 79 can also be used to decide a roughapplication position of the insulating resin 33.

[0316] Besides, the openings 79 shall be provided at such positions soas not to overlap with lead electrodes 41 or connecting electrodes 42 asseen from a first substrate 1 side. This configuration can reduce theinfluence due to non-existence of the covering member at the openings 79to a minimum.

[0317] Further, in such a liquid crystal display panel, it is preferableto provide a cap covering member 77 covering the openings 79 as shown inFIG. 36 on the openings 79. When the cap covering member 77 is provided,it is possible to prevent moisture permeation by the cap covering member77 even at the position of the openings 79 after the excessive resin andbubbles are exhausted. This eliminates a limit in position where theopenings 79 are provided, so that the openings 79 can be provided atarbitrary positions to inject the insulating resin 33 and exhaustbubbles effectively.

[0318] In addition, for example, when a transparent resin is used as theinsulating resin, the openings 79 are provided near the driving ICs 35and 36, and a black cap covering member 77 is provided thereon to shieldthe driving ICs 35 and 36 from light as in the nineteenth embodiment forprevention of a malfunction thereof.

[0319] Twenty-Second Embodiment: FIG. 37

[0320] Next, a twenty-second embodiment of the liquid crystal displaypanel of the invention will be described. FIG. 37 is a plan view of theliquid crystal display panel. In this drawing, the same numerals areassigned to portions corresponding to those in the eighth embodiment.

[0321] The twenty-second embodiment is characterized in that a coveringmember is provided in a manner to be divided for each driving IC. Theliquid crystal display panel of the twenty-second embodiment is alsoalmost the same as that of the above-described eighth embodiment exceptfor this point, and thus the description will be omitted or simplifiedexcept for the different point.

[0322] In this liquid crystal display panel, as shown in FIG. 37, aninsulating resin 33 is provided in a manner to be divided for eachdriving IC, and the covering member is provided also in a manner to bedivided for each driving IC, as covering members 51′. Then, based on theabove, the position where the lead electrodes are routed is changed sothat the lead electrodes are not routed through a portion where theinsulating resin 33 and the covering members 51′ are not providedbetween two driving ICs 35 outside a sealant 26.

[0323] The covering member on one side of the substrate provided in aplurality of divided portions as in this liquid crystal display panelcan decrease the stress exerted on the insulating resin 33 to prevent itfrom being broken or peeling off from a second substrate 6 even whenthere is a difference in thermal expansion coefficient between thecovering member 51′ and the substrate or even when the insulating resin33 thermally contracts or thermally expands, and therefore the moisturepermeability can stably be kept low. In addition, it becomes easy toexhaust bubbles forming in the insulating resin 33 and to apply theinsulating resin 33.

[0324] This effect becomes greater as the covering member is dividedinto smaller portions for provision. However, the covering member in toosmaller portions lowers the function of preventing moisture permeationitself, and thus it is preferable to provide the covering member in amanner to divide it for each driving IC in consideration of how to routelead electrodes 41.

[0325] First Modified Example of Embodiments: FIG. 38

[0326] Next, a first modified example of each of the above-describedembodiments will be described. FIG. 38 is a cross-sectional view,corresponding to FIG. 15, showing a cross section of the liquid crystaldisplay panel of the modified example.

[0327] This first modified example is an example in which the inventionis applied to a liquid crystal display panel being of an active matrixtype using a thin film transistor (TFT) and having driving ICs providedon an FPC. An example in which the modification is applied to theeleventh embodiment will be described.

[0328] In this liquid crystal display panel, as shown in FIG. 38, afirst substrate 1 is disposed on the lower side, and a second substrate6 is disposed on the upper side in order to provide the TFT as aswitching element on the first substrate 1. Further, on the firstsubstrate 1, a gate electrode 81, a gate insulating film 82, and asemiconductor layer 83 are formed in this order, and further a sourceelectrode 84 and a drain electrode 85 also serving as a displayelectrode are formed. Further, a semiconductor layer containing impurityions (not shown) is provided between the source electrode 84 and thedrain electrode 85 and the semiconductor layer 83. These constitute theTFT, and further an insulating film (not shown) is formed to preventdeterioration of characteristics of the TFT.

[0329] On the second substrate 6 opposite to the first substrate 1,there are provided a black matrix 8 for preventing light from leakingfrom the outer peripheral portion of a color filter and covering theperiphery of a display region, and the color filter which is composed ofa red (R) color filter 17, a green (G) color filter 18, and a blue (B)color filter (not shown). Then, on the color filter, a flattening film21 is provided, and further a second electrode 7 made of a transparentconductive film is provided on the flattening protective film 21.

[0330] In this liquid crystal display panel, the intersection of thedrain electrode 85 also serving as the display electrode connected tothe TFT and the second electrode 7 becomes a pixel portion. Further,alignment films (not shown) are provided on the faces on a liquidcrystal layer 25 side of the first substrate 1 and the second substrate6 to align the liquid crystal molecules of the liquid crystal layer 25in predetermined directions.

[0331] Besides, this liquid crystal display panel is a transmissiveliquid crystal display panel with an auxiliary light source (not shown)disposed under the first substrate 1, in which a first polarizing film11 is provided on the first substrate 1, and a second polarizing film 14is provided on the second substrate 6.

[0332] Then, a lead electrode 41, which is connected to the gateelectrode 81 or the source electrode 84 provided on the first substrate1, is provided on the first substrate 1 having a larger outer shape thanthat of the second substrate 6, and led outside a sealant 26 andconnected to an FPC 31. Then, driving ICs 35 are mounted on the FPC 31,and the periphery of the mounted portion is covered with a tapeautomated bonding (TAB) resin 69.

[0333] Also in this liquid crystal display panel, an insulating resin 33is provided on and around the lead electrode 41 to cover at least aportion of the lead electrode 41 outside the sealant 26 as in theeleventh embodiment. Further, the insulating resin 33 is similarlyprovided also on a portion of the FPC 31. Then, a polarizing film havinga size reaching the top of the insulating resin 33 is used as the secondpolarizing film 14 to be provided on the second substrate 6 and is usedalso as the insulating covering member, and a covering member 51 isfurther provided on the second polarizing film 14.

[0334] As compared to a passive matrix liquid crystal display panel withno switching element provided in each pixel portion, the active matrixliquid crystal display panel as this modified example can be maderesistant to electrolytic corrosion because it is possible to use metalas the material of the lead electrode 41 and cover a portion of the leadelectrode 41 with the insulating film constituting the switchingelement. However, when the moisture permeation preventing structure asin each of the above-described embodiments is applied to the activematrix liquid crystal display panel as described above, moisturepermeation from a portion where a pinhole or scratch forms in theinsulating film or the FPC 31 can be prevented for more reliableprevention of electrolytic corrosion.

[0335] Note that while the description is made here on the example usinga three-terminal active element, it is needless to say that the sameeffect can be attained even when using a two-terminal active element.

[0336] While the description is made here on the example in which thismodified example is applied to the eleventh embodiment, it is a matterof course that the modified example can be similarly applied also toother embodiments. This also applies to each of modified examplesdescribed below.

[0337] Second Modified Example: FIG. 39

[0338] Next, a second modified example of each of the above-describedembodiments will be described. FIG. 39 is a cross-sectional view,corresponding to FIG. 2, showing a cross section of the liquid crystaldisplay panel of the modified example.

[0339] This second modified example is an example in which the inventionis applied to a liquid crystal display panel having a configuration inwhich an FPC is directly connected to lead electrodes. FIG. 39 shows anexample in which the modification is applied to the second embodiment.

[0340] The invention, as shown in FIG. 39, can also be applied to aliquid crystal display panel in which an FPC 31 is directly connected toa lead electrode 41 without mounting a driving IC on a first substrate,and the driving IC is separately provided via the FPC 31.

[0341] In the case shown in FIG. 39, it is preferable that a thin filminsulating layer 22 is provided on the lead electrode 41 and on the FPC31 to cover at least a portion of the lead electrode 41 outside asealant 26, and further an insulating resin 32 is provided thereon. Evenin such a configuration that the FPC 31 is directly connected to thelead electrode 41, there is no recognition of occurrence of electrolyticcorrosion at the lead electrode 41 because the thin film insulatinglayer 22 has very low moisture permeability. As a matter of course, theembodiment using the covering member is also applicable to such a liquidcrystal display panel.

[0342] Third Modified Example: FIG. 40

[0343] Next, a third modified example of each of the above-describedembodiments will be described. FIG. 40 is a cross-sectional view,corresponding to FIG. 15, showing a cross section of the liquid crystaldisplay panel of the modified example.

[0344] This third modified example is characterized in that the outershape of a second substrate is aligned with the outer shape of a sealanton the side where the lead electrode is led out. FIG. 40 shows anexample in which the modification is applied to the eighth embodiment.

[0345] In the liquid crystal display panel in each of theabove-described embodiments, it is preferable that the outer shape of asecond substrate 6 is aligned with the outer shape of a sealant 26 atleast on the side where lead electrode 41 is led out as shown in FIG.40. The insulating resin and the thin film insulating layer are to beprovided on the side where the lead electrode is led out in accordancewith the characteristics of each embodiment. The above-mentionedconfiguration, however, can eliminate a narrow space between a firstsubstrate 1 and the second substrate 6 outside the sealant 26, so thatit is unnecessary to form the insulating resin and the thin filminsulating layer in the narrow space, thus facilitating formationthereof. Further, it is also eliminated that the insulating resinprovided in the space between the first substrate 1 and the secondsubstrate 6 thermally expands or thermally contracts to deform thesubstrates and accordingly change the width of the gap, that is, thethickness of a liquid crystal layer 25 to thereby adversely affectdisplay, so that the display quality can be improved.

[0346] Other Modified Examples

[0347] The description will be made on other modified examplesapplicable to the above-described embodiments.

[0348] First, the invention is applicable also to liquid crystal displaypanels using a guest-host liquid crystal, a scattering-type liquidcrystal, and a fluorescent liquid crystal, which are capable of displaywithout using a polarizing film. When there is a need to preventinfluence of ultraviolet rays emitted during formation of the thin filminsulating layer, it is preferable to use a transparent film having anultraviolet absorbing material or ultraviolet reflecting material.

[0349] While the description is made here on the example using the COGmethod in which the driving ICs are mounted on the substrate, theinvention is, of course, effective for measures against electrolyticcorrosion in the case using a TAB mounting method, a COB mountingmethod, and a COF mounting method. For example, in the case of the TABmounting method or COF mounting method in which the driving ICs aremounted on the FPC, the invention is effective also for protection ofcircuits around the driving ICs, because the thin film insulating layerprevents moisture permeation into the driving ICs.

[0350] While no example is shown here in which chip parts such as aresistor and so on are mounted directly on the first substrate or thesecond substrate, the thin film insulating layer which covers chip partsand connecting portions concurrently with the lead electrodes canprevent corrosion and electrolytic corrosion of the chip parts andconnecting portions concurrently with electrolytic corrosion of the leadelectrodes even when the chip parts are mounted directly.

[0351] Further, when the thin film insulating layer is provided on thepolarizing film, the refractive index of the thin film insulating layercan be controlled to lower the surface reflectance for improved displayquality of the liquid crystal display panel.

[0352] Further, it is needless to say that the above-describedembodiments may be appropriately combined together to constitute aliquid crystal display panel having their characteristics.

[0353] Industrial Applicability

[0354] As has been described, according to the liquid crystal displaypanel of the invention, the insulating covering member is provided tocover at least the portions of the lead electrodes outside the sealantand overlap with a portion of the second substrate so as to fullyprevent moisture permeation into the lead electrode and preventelectrolytic corrosion from occurring in the lead electrode even whenthe panel is operated for a long time in an environment of a hightemperature and high humidity, which enables improved display qualityand reliability of the liquid crystal display panel.

[0355] Further, according to a fabricating method of the liquid crystaldisplay panel of the invention, such a liquid crystal display panel canbe easily fabricated.

What is claimed is:
 1. A liquid crystal display panel, in which a firstsubstrate and a second substrate are opposed to each other with apredetermined gap provided therebetween, a liquid crystal layer issealed in the gap with a sealant, pixel portions are formed byelectrodes, said electrodes being provided on said first substrate andon said second substrate to oppose to each other via said liquid crystallayer, and lead electrodes for applying electric signals to saidelectrodes forming said pixel portions are provided at least on saidfirst substrate, wherein an insulating covering member is provided tocover at least portions of said lead electrodes outside said sealant andoverlap with a portion of said second substrate.
 2. The liquid crystaldisplay panel according to claim 1, wherein an integrated circuitelement mounted on said lead electrodes is provided, and said insulatingcovering member is provided also on said integrated circuit element. 3.The liquid crystal display panel according to claim 2, wherein aflexible connecting board connected to said integrated circuit elementis provided, and said insulating covering member is provided also atleast on a portion of said flexible connecting board.
 4. The liquidcrystal display panel according to claim 1, wherein a flexibleconnecting board connected to said lead electrodes is provided, and saidinsulating covering member is provided also at least on a portion ofsaid flexible connecting board.
 5. The liquid crystal display panelaccording to claim 1, wherein a flexible connecting board for connectingsaid liquid crystal display panel to an external circuit is provided,and said insulating covering member is provided on both faces of saidflexible connecting board.
 6. The liquid crystal display panel accordingto claim 1, wherein said insulating covering member is provided also ona side face of said second substrate.
 7. The liquid crystal displaypanel according to claim 1, wherein said insulating covering member isprovided also on a side face of said first substrate or on a face ofsaid first substrate opposite to a face provided with said leadelectrodes.
 8. The liquid crystal display panel according to claim 1,wherein a polarizing film is provided on at least one of said firstsubstrate and said second substrate, and said insulating covering memberis provided also on said polarizing film.
 9. The liquid crystal displaypanel according to claim 1, wherein a polarizing film is provided on atleast one of said first substrate and said second substrate, and whereinsaid insulating covering member is provided also between said polarizingfilm and said substrate provided with said polarizing film.
 10. Theliquid crystal display panel according to claim 6, wherein a reflectinglayer is provided on one of said first substrate and said secondsubstrate.
 11. The liquid crystal display panel according to claim 7,wherein a reflecting layer is provided on one of said first substrateand said second substrate.
 12. The liquid crystal display panelaccording to claim 1, wherein an insulating resin is provided on saidinsulating covering member.
 13. The liquid crystal display panelaccording to claim 12, wherein a second insulating covering member isprovided on said insulating resin.
 14. The liquid crystal display panelaccording to claim 1, wherein said insulating covering member is aninsulating layer formed in a vacuum condition.
 15. The liquid crystaldisplay panel according to claim 14, wherein said insulating coveringmember is an insulating layer containing silicon.
 16. The liquid crystaldisplay panel according to claim 14, wherein said insulating coveringmember is an insulating layer which is made of metal oxide.
 17. Theliquid crystal display panel according to claim 1, wherein saidinsulating covering member is smaller in thickness than said liquidcrystal layer.
 18. The liquid crystal display panel according to claim1, wherein said insulating covering member has a structure in which twoor more different kinds of insulating films are laminated.
 19. Theliquid crystal display panel according to claim 1, wherein saidinsulating covering member is 200 nm to 500 nm in thickness.
 20. Theliquid crystal display panel according to claim 1, wherein an insulatingresin is provided to cover at least portions of said lead electrodesoutside said sealant, and said insulating covering member is providedthereon.
 21. The liquid crystal display panel according to claim 20,wherein a portion where said first substrate, said insulating resin,said second substrate, and said insulating covering member overlap oneanother as seen from said first substrate side, is provided.
 22. Theliquid crystal display panel according to claim 20, wherein said firstsubstrate and said insulating covering member are bonded together withsaid insulating resin.
 23. The liquid crystal display panel according toclaim 20, wherein said insulating covering member is bonded to both saidfirst substrate and said second substrate with said insulating resin.24. The liquid crystal display panel according to claim 20, wherein anintegrated circuit element mounted on said lead electrodes is provided,and said insulating resin is provided between said integrated circuitelement and said sealant.
 25. The liquid crystal display panel accordingto claim 24, wherein said insulating covering member has portionsoverlapping with said insulating resin, said integrated circuit element,and said second substrate, respectively as seen from said firstsubstrate side.
 26. The liquid crystal display panel according to claim24, wherein said insulating covering member is in contact with both saidintegrated circuit element and said second substrate.
 27. The liquidcrystal display panel according to claim 24, wherein a flexibleconnecting board for connecting said integrated circuit element and anexternal circuit is provided.
 28. The liquid crystal display panelaccording to claim 27, wherein said insulating covering member hasportions overlapping with said insulating resin, said second substrate,and said flexible connecting board, respectively as seen from said firstsubstrate side.
 29. The liquid crystal display panel according to claim27, wherein said insulating covering member has portions overlappingwith said insulating resin, said integrated circuit element, said secondsubstrate, and said flexible connecting board, respectively as seen fromsaid first substrate side.
 30. The liquid crystal display panelaccording to claim 20, wherein a flexible connecting board directlyconnected to said lead electrodes is provided.
 31. The liquid crystaldisplay panel according to claim 30, wherein said insulating coveringmember has portions overlapping with said insulating resin, said secondsubstrate, and said flexible connecting board, respectively as seen fromsaid first substrate side.
 32. The liquid crystal display panelaccording to claim 20, wherein said insulating resin is composed of atleast two kinds of resins.
 33. The liquid crystal display panelaccording to claim 20, wherein said insulating covering member has athermal expansion coefficient equal to that of said first substrate orsaid second substrate.
 34. The liquid crystal display panel according toclaim 20, wherein a polarizing film is provided, said polarizing filmbeing used as said insulating covering member.
 35. The liquid crystaldisplay panel according to claim 20, wherein a polarizing film isprovided, and said insulating covering member is provided to be incontact with said polarizing film.
 36. The liquid crystal display panelaccording to claim 20, wherein a polarizing film is provided, and saidinsulating covering member is provided to have a predetermined gap withsaid polarizing film.
 37. The liquid crystal display panel according toclaim 20, wherein said insulating covering member is formed of glass.38. The liquid crystal display panel according to claim 20, wherein saidinsulating covering member is formed of plastic.
 39. The liquid crystaldisplay panel according to claim 38, wherein said insulating coveringmember has a gas barrier layer or a moisture blocking layer.
 40. Theliquid crystal display panel according to claim 20, wherein saidinsulating covering member is formed of ceramics.
 41. The liquid crystaldisplay panel according to claim 20, wherein said insulating coveringmember is formed of metallic material.
 42. The liquid crystal displaypanel according to claim 41, wherein a second insulating covering memberis provided on said insulating covering member.
 43. The liquid crystaldisplay panel according to claim 42, wherein said second insulatingcovering member is an anodic oxide layer of said metallic material. 44.The liquid crystal display panel according to claim 20, wherein saidinsulating resin is constituted of an epoxy resin.
 45. The liquidcrystal display panel according to claim 20, wherein said insulatingresin is constituted of an ultraviolet curing resin.
 46. The liquidcrystal display panel according to claim 20, wherein said insulatingresin is constituted of a silicon resin.
 47. The liquid crystal displaypanel according to claim 20, wherein said insulating resin has a lightabsorption material.
 48. The liquid crystal display panel according toclaim 20, wherein said insulating resin is constituted of a firstinsulating resin for covering at least portions of said lead electrodesand a second insulating resin for sealing a space formed by said firstinsulating resin, said first substrate, and said second substrate. 49.The liquid crystal display panel according to claim 20, wherein saidinsulating covering member has a face in contact with said insulatingresin and in a direction perpendicular to said first substrate.
 50. Theliquid crystal display panel according to claim 20, wherein saidinsulating covering member has an opening.
 51. The liquid crystaldisplay panel according to claim 50, wherein said opening is provided ata portion not overlapping with said lead electrodes.
 52. The liquidcrystal display panel according to claim 50, wherein said opening is anopening for introducing said insulating resin, and said insulating resinhas a swollen structure in said opening.
 53. The liquid crystal displaypanel according to claim 20, wherein said insulating covering member hasa U-shaped cross section and is provided such that said first substrateis in contact with the inside of the letter U.
 54. The liquid crystaldisplay panel according to claim 53, wherein said insulating coveringmember is in contact with at least two faces out of six faces being topand bottom, right and left, and front and back faces of said firstsubstrate.
 55. The liquid crystal display panel according to claim 53,wherein said insulating covering member has a substrate groove forfitting said first substrate therein.
 56. The liquid crystal displaypanel according to claim 53, wherein a flexible connecting board forconnecting said liquid crystal display panel to an external circuit isprovided, and wherein said insulating covering member is provided withan opening for passing said flexible connecting board therethrough. 57.The liquid crystal display panel according to claim 20, wherein aflexible connecting board for connecting said liquid crystal displaypanel to an external circuit is provided, and wherein said insulatingresin is provided also at least on respective portions of both faces ofsaid flexible connecting board.
 58. The liquid crystal display panelaccording to claim 20, wherein said insulating covering member comprisesa black member and is used as a panel cover to be provided on an outerperiphery of a display region constituted of said pixel portions. 59.The liquid crystal display panel according to claim 20, wherein aflexible connecting board for connecting said liquid crystal displaypanel to an external circuit is provided, and a portion of said flexibleconnecting board is used as said insulating covering member.
 60. Theliquid crystal display panel according to claim 1, wherein an outershape of said second substrate aligns with an outer shape of saidsealant at least on a side where said lead electrodes are led out to theoutside of said sealant.
 61. The liquid crystal display panel accordingto claim 20, wherein a second insulating covering member is provided onsaid insulating covering member.
 62. The liquid crystal display panelaccording to claim 1, wherein an integrated circuit element mounted onsaid lead electrodes is provided, and said insulating covering member isprovided also on said integrated circuit element and is colored in blackon said integrated circuit element.
 63. The liquid crystal display panelaccording to claim 20, wherein an outer peripheral wall for preventingsaid insulating resin from flowing out is provided on at least a portionof an outer periphery of a region where said insulating resin is to beprovided.
 64. The liquid crystal display panel according to claim 20,wherein said insulating covering member is provided in a plurality ofdivided parts.
 65. The liquid crystal display panel according to claim20, wherein said insulating covering member is 80 μm to 150 μm inthickness.
 66. A method for fabricating a liquid crystal display panel,comprising: a step of preparing a liquid crystal display panel in whicha first substrate and a second substrate are opposed to each other witha predetermined gap provided therebetween, a liquid crystal layer issealed in the gap with a sealant, pixel portions are formed byelectrodes, said electrodes being provided on said first substrate andon said second substrate to oppose to each other via said liquid crystallayer, and lead electrodes for applying electric signals to saidelectrodes forming said pixel portions are provided at least on saidfirst substrate; a step of mounting an integrated circuit element or aflexible connecting board on said lead electrodes; a resin applying stepof applying an insulating resin onto said lead electrodes at leastoutside said sealant; an insulating covering member disposing step ofdisposing an insulating covering member on said insulating resin tocover at least portions of said lead electrodes outside said sealant andoverlap with a portion of said second substrate; and a curing step ofcuring said insulating resin, said steps being performed in this order.67. The method for fabricating a liquid crystal display panel accordingto claim 66, further comprising: prior to said insulating coveringmember disposing step, a step of disposing a polarizing film on saidfirst substrate or on said second substrate.
 68. The method forfabricating a liquid crystal display panel according to claim 66,further comprising: between said insulating covering member disposingstep and said curing step, a low-viscosity insulating resin applyingstep of applying a low-viscosity insulating resin lower in viscositythan said insulating resin to seal a space formed by said insulatingresin, said first substrate, and said second substrate, wherein saidcuring step is a step of curing said insulating resin and saidlow-viscosity insulating resin.
 69. The method for fabricating a liquidcrystal display panel according to claim 66, further comprising: priorto said resin applying step, a low-viscosity insulating resin applyingstep of applying a low-viscosity insulating resin lower in viscositythan said insulating resin to at least a portion of a space between saidfirst substrate and said second substrate outside said sealant.
 70. Themethod for fabricating a liquid crystal display panel according to claim69, further comprising: between said low-viscosity insulating resinapplying step and said resin applying step, a low-viscosity insulatingresin curing step of curing said low-viscosity insulating resin.
 71. Themethod for fabricating a liquid crystal display panel according to claim66, further comprising: prior to said resin applying step, an outerperipheral wall setting step of providing an outer peripheral wall forpreventing said insulating resin from flowing out, on at least a portionof an outer periphery of a region to which said insulating resin is tobe applied.
 72. A method for fabricating a liquid crystal display panel,comprising: a step of preparing a liquid crystal display panel in whicha first substrate and a second substrate are opposed to each other witha predetermined gap provided therebetween, a liquid crystal layer issealed in the gap with a sealant, pixel portions are formed byelectrodes, said electrodes being provided on said first substrate andon said second substrate to oppose to each other via said liquid crystallayer, and lead electrodes for applying electric signals to saidelectrodes forming said pixel portions are provided at least on saidfirst substrate; a step of mounting an integrated circuit element or aflexible connecting board on said lead electrodes; and an insulatingcovering member forming step of forming an insulating covering member bya vacuum sputtering or a chemical deposition (CVD) method to cover atleast portions of said lead electrodes outside said sealant and overlapwith a portion of said second substrate, said steps being performed inthis order.
 73. The method for fabricating a liquid crystal displaypanel according to claim 72, wherein said insulating covering memberforming step is performed at a temperature equal to or lower than 150°C..
 74. The method for fabricating a liquid crystal display panelaccording to claim 72, further comprising: prior to said insulatingcovering member forming step, a polarizing film disposing step ofdisposing a polarizing film on said first substrate or on said secondsubstrate.
 75. The method for fabricating a liquid crystal display panelaccording to claim 74, wherein said polarizing film disposing step is astep of disposing a polarizing film having a protective film, saidmethod further comprising: after said insulating covering member formingstep, a step of removing said protective film of said polarizing film.76. The method for fabricating a liquid crystal display panel accordingto claim 72, further comprising: prior to said insulating coveringmember forming step, a step of performing a plasma treatment using anyone of an oxygen plasma, an inert gas, an oxygen gas, and a nitrogengas, or a mixture gas of two or more kinds of these for at least aregion where said insulating covering member is to be provided.